Today, most of them are invisible – diverted into underground channels or filled in – but their traces remain beneath the city’s streets, in archaeological remains, and in place names that carry the memory of flowing water.

Attica, a plain surrounded by mountains, was historically a place where waters converged. Mile after mile of brooks, streams, and rivers crossed the area between Parnitha, Penteli, and Hymettos. Then came the concrete and the asphalt. It is estimated that more than 300 miles of waterways have been diverted underground to the present day.

Rivers that turned into streets

Many of today’s central streets and avenues in Athens were laid out along the natural courses once carved by rivers and streams. Excavations have shown that most of the city’s modern streets conceal a filled-in streambed or an underground river. Studies indicate that in 1945, the open waterways had a total length of about 800 miles. Toda,y only 270 miles remain – a dramatic decline.

Yet, despite so much having been lost, traces of old Athens still endure – and some can still be experienced. The hidden rivers are only one part of the city’s many secrets:

🎧 Athens in your headphones – a journey at your own pace

With our audio guide on VoiceMap you can experience Athens in a new way. The tour leads you through the city’s hidden layers – its tucked-away alleys, overlooked buildings, and stories rarely found in guidebooks. You set the pace yourself: follow the route on the ground in Athens with the app as your companion, or listen as a virtual walk wherever you are.

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In the 1950s, during the era of the so-called antiparochi, and later for the sake of car traffic, rivers were treated as obstacles rather than as parts of the Attic landscape.*

* Antiparochi (αντιπαροχή): the post-war system that shaped Athens, in which landowners allowed developers to build apartment blocks on their plots in exchange for a number of the finished flats.

According to figures often repeated in the Greek press, the numbers speak for themselves: after World War II, about 25 percent of the Athens basin was covered by roads and buildings. After 1975, that share had risen to 75 percent.

Kifissos – from myth to motorway

Kifissos, flowing west of Athens, is the largest and best-known river of Attica. Ancient authors mentioned it more than two thousand years ago. For the Athenians of antiquity, Kifissos was sacred – a source of life for the great, fertile plain.

Like several other rivers, Kifissos was personified in mythology by a god of the same name. He was counted among the lesser deities of Attica, an allegorical figure of the river itself – at times praised for the water he brought to the fertile plain, at other times feared for the floods he could unleash.

Along its course also lay Elaionas, the wide area of Athenian olive groves, where the waters of Kifissos irrigated the trees that produced the highly prized local olive oil, one of the city’s most important exports in antiquity.

The Sacred Way, Iera Odos, crossed the Kifissos on its route to Eleusis, and several remains from antiquity can still be seen today – now wedged in between industrial complexes, warehouses, and busy highways.

In modern times, Kifissos has become associated with the motorways and industrial zones that follow its course. Large sections of the river have been channelled, and its waters are burdened by the city’s pollution. Today, the Kifissos riverbed is considered one of the major open environmental problems of the Athens basin.

Ilissos – the stream of philosophy and nymphs

The Ilissos rises on Mount Hymettus and flows along the eastern edge of Athens. Its current is at its strongest in winter and spring. For the Athenians of antiquity, it was a sacred river. Along its banks stood altars dedicated to many gods. Here, the Lesser Mysteries (Mikra Mysteria) were held – sacred rites connected both to the Great Mysteries of Eleusis and to Dionysian ceremonies. By the Ilissos were also sanctuaries of the Nymphs and of Pan, and Plato has Socrates hold dialogues by the stream.

Ilissos, the largest of today’s hidden rivers of Athens, once flowed outside the ancient city walls and was crossed by several bridges, of which only one survives today. The others were destroyed when the Ilissos was led underground in the 1930s. This took place under the dictatorship of Metaxas, who is said to have marked the beginning of the covering with the symbolic words: “Here we bury the Ilissos.”

Yet traces of the river remain in the urban landscape. The arched bridge built by King Otto still stands, even though it is now itself overbuilt by busy motorways.

Right next to King Otto’s bridge stands a well-preserved rock relief of the god Pan. Here, too, the church of Agia Foteini was built, beside the ancient spring of Kallirrhoe. On the small island of Vatrachonisi – the “Frog Island” – where the river splits into branches, the vegetation still grows thick, a last glimpse of the green belt that once lined the stream. It was at Vatrachonisi that the Ilissos formed rapids and small waterfalls, sacred and widely celebrated in antiquity. We have written about these places in our series The Secret Athens →

But the stream is not entirely lost: today it can still be followed underground. Together with the Alter Exploring Team, we have walked through the subterranean passages of the Ilissos, all the way down towards Kallithea.

Eridanos – a small stream with a long history

Eridanos is a relatively small stream, but it has played an important role in the history of Athens. Its source lies on Mount Lycabettus, and it crosses the city on its way to Kerameikos, where it can still be seen above ground. From there, it follows the Sacred Way, Iera Odos, before eventually joining the Kifissos. Along its course in antiquity, both houses and workshops developed, and the stream soon became an integral part of everyday life in Athens.

Gradually, the Eridanos disappeared beneath fill and construction. However, today it can still be seen in two places: in the archaeological site of Kerameikos, where a two-meter-wide stretch of its bed has been uncovered, and at Monastiraki. There it first appears outside on the square, somewhat inconspicuously behind a fence, and then inside the station behind a sloping glass wall. Here, other finds are also displayed, brought to light during the construction of the new Metro station in the 1990s.

Forgotten streams with peculiar names

In addition to the Kifissos, Ilissos, and Eridanos, the city was historically crossed by many other waterways. Some had their sources on Lycabettus, others in the Tourkovounia hills to the northeast, and they carried their waters through the areas that today form the very heart of the city.

One of these streams is the Podoniftis – the “Foot Washer” – with its sources on Mount Penteli, north of Athens. It still flows above ground for about four kilometers. We have traced the Podoniftis before in our own explorations →

Other ancient streams included the Voidopniktis – literally the “Ox Drowner” – and the Kyklovoros, whose peculiar name still puzzles linguists. They once flowed where we now walk along well-known streets such as Stadiou and Akadimias, or through today’s densely built-up districts like Patisia and Kypseli. The names that remain are reminders that Athens was once a network of rivers, brooks and streams that gave life to the Attic landscape.

Uncovering – visions and risks

There is sometimes talk of Athens reclaiming its rivers, of freeing them from the concrete and making them visible again. Advocates point out that reopening waterways could reduce the risk of flooding, create new green recreational spaces, and restore access to a more natural urban environment.

According to the European Environment Agency, restored urban streams can strengthen biodiversity and improve water quality. They can also help lower temperatures in densely built-up areas – the so-called urban heat island effect, when the city becomes warmer than its surroundings due to asphalt and concrete. At the same time, they can bring social and economic benefits – from health and quality of life to investment, tourism, and rising property values.

But behind the vision of open waterways lies an inconvenient reality that cannot be ignored. Many of Athens’ streams were covered over to protect the public from sewage and other sanitary risks. According to serious voices in the debate, these problems must be solved first – otherwise reopening risks becoming a danger rather than a gift.

The river network of Attica

Sources

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Hidden attractions in Athens

Athens is a city built in layers – marked by ancient civilizations, hard-won conquests, shifting beliefs, and the daily rhythms of life that still pulse through its streets today. Its buildings and alleys echo with the presence of many eras: Archaic and Classical Athens, the Hellenistic period, Roman occupation, a thousand years of Byzantine rule, Ottoman domination, Frankish control, the 19th-century War of Independence, and finally, the formation of the modern Greek state.

Sometimes, these layers are easy to spot – a marble column built into a later wall, a hidden courtyard tucked behind a noisy street. Other times, they lie buried, waiting to be uncovered by those who know where to look.

But Athens is not a museum. It is a living city, where past and present continuously intertwine. The same streets once walked by philosophers and revolutionaries now bustle with cafés, shops, and everyday Athenian life. Every step through Athens is a step across centuries.

Ancient aqueduct in the National Garden

Our first stop today, through lesser-known attractions in Athens, is the aqueduct of Pisistratus, built in the 6th century BCE, which still irrigates the central city park – the National Garden. We begin our walk at the park’s northern entrance, along Vasilissis Sofias Avenue.

Just a few steps from the park’s northern entrance on Vasilissis Sofias Avenue, you’ll find a small pond after roughly 65 feet. It may look quiet and unassuming, but it holds a fascinating secret: this is where water from an ancient aqueduct gathers before flowing onward to nourish the garden’s lush greenery.

This remarkable structure, known as the Peisistratos Aqueduct, dates back to the 6th century BCE and remains in operation today. It runs underground for about 4 miles at a depth of 30 – 40 feet. The aqueduct begins at the base of Mount Hymettos, the striking mountain range east of Athens, and follows the natural contours of the land toward the city center.

The pond also marks the garden’s highest point. From here, the water is directed into a branching system that irrigates the park’s trees and vegetation. It’s a quiet yet tangible link between ancient Athens and the modern metropolis.

Ancient remnants in the National Garden

The National Garden is truly a peaceful green space amid the city’s bustle – an oasis and a place to breathe in modern Athens. But the site also has deep historical roots. Already in antiquity, the philosopher and botanist Theophrastus had a private garden here. In the mid-19th century, a royal park was established on the same site at the initiative of Queen Amalia. At that time, it was known as the Royal Garden.

Today, known as the National Garden, it is a lush public refuge filled with winding paths, tall palm trees, and an unexpectedly rich birdlife – open to all, every day of the year.

To reach the next stop on our tour, we need to walk through the entire garden, from the northern pond to one of the southern exits. There, in a somewhat hidden corner, nestled among several other Roman remnants, lies a rather overlooked monument.

It is a massive architrave, a marble beam that for centuries adorned Hadrian’s great reservoir at Dexameni Square in Kolonaki. In the first part of our series, we explored the area around Dexameni, where this architrave once stood in its original place.

At the end of the 18th century, it was removed from its original location by the Ottoman ruler Hatzis Ali Haseki, who used parts of ancient monuments as building material for his defensive wall.

This particular marble block was then installed as a decorative top element above one of the wall’s seven city gates – the so-called Boubounistra Gate. After the Greek War of Independence, when the wall was torn down, it was eventually placed in its current location in the National Garden, without any form of signage. In the 19th century, it was common for ancient fragments to be reused as ornamental features in gardens, in a spirit of romanticism and decoration.

The marble architrave bears a Latin inscription stating that the aqueduct in Athens was begun by Emperor Hadrian and later completed and inaugurated by his adopted son, Antoninus Pius.

Hadrian’s Athens

Nearly two thousand years ago, Athens stood at the threshold of a dramatic transformation. The city was already ancient, but Emperor Hadrian sought to breathe new life into it. A devoted philhellene – a lover of Greek culture – Hadrian, though a conqueror, saw Athens as the cultural capital of the East, a place where Roman power and Hellenic heritage could converge.

During his reign, a new district rose in Athens, filled with monumental buildings, libraries, and grand residences for the city’s aristocracy. The era of Pax Romana became a golden age of architecture for the city, and no one played a greater role in reshaping it than Hadrian himself. He financed and oversaw many of the major projects – among them Hadrian’s Arch and the long-delayed completion of the great Temple of Olympian Zeus.

We’ve explored the temple and shared some of the lesser-known stories of the Olympieion in a previous article.

Now, we leave those iconic landmarks behind and make our way toward our next stop: King Otto’s arched stone bridge over the Ilisos River, today hidden beneath one of the busiest intersections in modern Athens.

The arch bridge over Ilisos

If you walk around the entire archaeological site of the Olympieion and follow the fence along its southern side, you’ll come out onto Athanasiou Diakou Street. Continuing along that road, you’ll soon reach one of the city’s busiest intersections, where several major thoroughfares converge.

Well hidden beneath the busy traffic of this intersection lies a stone arch bridge, built in the mid-1800s on the initiative of King Otto, Greece’s first monarch. It once spanned the Ilisos River – one of Athens’ largest waterways.

Today, the river runs underground, but the remaining channel has been overtaken by nature: dense, almost impenetrable vegetation spreads like a small, tangled jungle in the heart of the city. The central section of the riverbed is still known as Vatrachonisi/Frog Island – even though it’s no longer an island in the true sense. In ancient times, Frog Island was a sacred place where many gods, demigods, and nymphs were worshipped.

Relief of the God Pan

Just past the bridge, a small paved walkway branches off to the left, leading down into the overgrown riverbed. The small Orthodox chapel located there today is dedicated to Saint Photini. In ancient times, the sacred spring of Kallirhoe flowed nearby – its waters believed to be holy. The courtyard in front of the chapel is a great place to sit for a while and escape the roar of traffic just above.

About halfway down the walkway toward Agia Foteini, a barely visible path breaks off to the right, cutting through the vegetation and heading straight toward the cliff face. A sign indicates that the hollow in the rock was once a cult site dedicated to the god Pan. Numerous artifacts have been found here to support that interpretation.

Carved into the rock face is an ancient relief of the god Pan – still visible today, though hard to spot unless you know exactly where to look. In my experience, it’s easiest to make out when the afternoon sun hits the cliff from the west, casting shadows that bring out the contours. Time and city pollution have worn heavily on the original carving, and it’s worth noting that the entire cliff was once nearly demolished to widen the road above. It was only thanks to the persistent efforts of local archaeologists that the decision was reversed at the last moment.

To reach the next stop on our route through lesser-known attractions in Athens, we’ll need to cross over to the other side of the city center. We’ll walk through Plaka and Monastiraki, then follow Athinas Street toward Omonia Square – until we reach Athens’ Central Market.

Varvakios Agora – Athens Central Market

Athens Central Market, known as Varvakios Agora, is a bustling hub of commerce in the heart of the city. It first opened in 1886 and has been operating ever since. The air here is thick with the scents of spices, fresh fish, meat, cheese, fruit, and warm bread, blending with the shouts of vendors and the chatter between loyal customers and curious passersby.

During holidays – especially Easter – the market teems with Athenians stocking up for celebratory meals, reflecting the city’s vibrant food culture. The area around the market is equally lively, with small shops and stalls selling everything from dried fruit and nuts to soaps, baskets, and kitchen tools – offering an authentic glimpse into everyday life in Athens.

St. John on the Column

Not far from the meat and fish halls, right in the heart of the market district on Evripidou Street, stands the small chapel of Agios Ioannis tis Kolonas – St. John on the Column. A single ancient Corinthian column rises straight through the roof, making this spot a truly unique feature in the cityscape.

The chapel is believed to be around 1,500 years old, built on the ruins of an earlier temple dedicated to Asclepius, the god of healing. Even into modern times, visitors have tied colored threads around the column, secured with wax – a ritual performed in hope of relief from fever and illness. A hidden, sacred little chapel nestled in an area that, until the 19th century, was mostly farmland and open fields.

Beyond the city center

From King Otto’s stone bridge, the Ilisos River continues its journey underground all the way to its mouth in Faliro, near Piraeus. As shown in the video below, the Greek Expedition joined a striking and thrilling exploration beneath the Greek capital’s roads and buildings. The underground tour was organized in collaboration with the Alter Exploring Team, led by speleologist and civil engineer Panagiotis Deuteraios.

Athens behind the facades

The Ilisos River may be hidden today, but it still whispers beneath the city – quietly, unnoticed, yet never entirely silent. Like other traces we’ve followed on this tour, it remains beneath the surface – a reminder that Athens isn’t just something you see, but something you gradually uncover, layer by layer.
And perhaps it’s in the quiet in-between spaces – where history isn’t marked or signposted – that you come closest to the city itself.

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A living oasis of biodiversity

Podoniftis is not just a historic waterway — it’s also a thriving ecosystem. In its clear waters, fish can often be seen gliding by. Frogs rest on the stones near the banks, while herons and other water birds are frequent visitors along the shore. On spring and summer nights, the air fills with the song of nightingales, and the tiny scops owl, known as “Gionis” in Greek, can be heard hooting in the dark.

Few other places in Athens offer such a close encounter with nature’s quiet spectacle. It’s a striking contrast — between the wild, green world of Podoniftis and the noisy, urban landscape that surrounds it.

Origin and course

Podoniftis has its source on the southwestern slopes of Mount Penteli and flows through areas such as Patima, Vrilissia, Chalandri, and Filothei, before winding its way through Nea Ionia, Nea Filadelfia, and Patisia. Along its path, it has been shaped by both natural forces and human activity. Much of the stream has been covered over by urban development, but certain sections – especially between Nea Ionia and Ano Patisia – remain untouched, open, and accessible as walking trails.

Visiting Podoniftis feels like stepping into another world. Along its banks, you can hear the soft murmur of water that has flowed for thousands of years. It’s a place where time seems to stand still, where nature whispers its ancient stories to those who listen.

Near the intersection of Acharnon and Dekelias in Patisia, however, Podoniftis disappears from view once more, directed into an underground channel. From there, it continues toward Kifissos – the largest river in Attica – where it eventually merges as one of its many tributaries.

Kifissos flows both through and beneath the urban landscape of southwestern Athens, eventually emptying into the Bay of Faliro and the Saronic Gulf. During the 19th and 20th centuries, numerous industries and facilities were established along its banks, particularly in Athens’ heavy industrial zones, leading to severe pollution. Despite repeated cleanup efforts, Kifissos is still considered one of the most burdened rivers in the region. Much of its course today is flanked by major roadways dominated by asphalt, exhaust fumes, and concrete, rather than fresh air and green spaces.
More on Kifissos coming soon on our blog – right here →

Flooding and the threat of being led entirely underground

Historically, Podoniftis has been prone to flooding, especially during heavy rainfall. In 1994, Athens was hit by a severe flood in which Podoniftis overflowed its banks. Seventeen people lost their lives in the disaster, drawing attention to the stream’s risks and vulnerability.

To address these risks, additional stream sections have been covered, which, unfortunately, has resulted in the loss of many natural habitats. Today, voices call for the complete covering of Podoniftis to prevent future disasters. At the same time, several environmental organizations and local groups are fighting to preserve the stream’s open sections and its ecological value.

Administrative challenges hinder development

One reason the area around Podoniftis hasn’t been developed into a pleasant walking route, like the one along the Chalandri stream, is that it runs through four different municipalities: Athens, Nea Ionia, Nea Filadelfeia, and Nea Chalkidona. These municipalities have struggled to agree on coordinated measures to improve and maintain the area.

A stream with shifting moods

Podoniftis is not a stream that always behaves the same way. During dry periods, it flows quietly and gently, as if holding its breath. The water then moves slowly, clear and calm, almost meditative in its rhythm. But after heavy rains, it reveals a very different side.

The water can rise within just a few hours, rushing with a force that feels both alive and dangerous. The once gentle murmur turns into a roar, and the usually peaceful riverbed transforms into a thundering surge of churning, swirling water. In those moments, it becomes clear why debates over covering the stream and ensuring flood safety never fade from the local conversation. It’s as if Podoniftis wants to remind the city of its primal power, of the fact that it has been here long before the fleeting concrete.

A jungle in the heart of the city

Walking there in daylight is an experience in itself. Sunlight filters through the foliage, casting patterns of light and shadow along the banks. Small lizards bask on warm stones, while butterflies and dragonflies dance across the water’s surface. The soundscape is filled with birdsong, yet faint traffic noise in the distance reminds you just how close the city still is. The scent of damp earth and greenery is distinct, especially after rain, when the air feels heavy but fresh. It’s a place for rest, but also for discovery – especially for those who enjoy being immersed in nature.

In the first blue light of dawn, or during the reddish fade of dusk, Podoniftis takes on a tone all its own. The colors soften, contrasted by bursts of bird activity – swallows, blackbirds, and magpies shifting places in the trees. At times, mist drifts over the water, giving the landscape an almost cinematic quality. The light is gentle, and walking here often feels meditative.

Under the full moon, the still water takes on a silvery sheen, and shadows from the overgrown trees stretch across the stream like fleeting, dreamlike memories. The air grows cooler, birdsong fades, replaced by the soft calls of the scops owl, while the movement of the water becomes more pronounced, more present. It’s a place that invites contemplation — a nocturnal dialogue between human and nature, quiet and timeless in a city that otherwise never sleeps.

The name “Podoniftis” – an etymological riddle

The name “Podoniftis” is believed to derive from the Greek words pous (foot) and nipto (to wash), possibly meaning “the foot-washer.” Several theories exist: one suggests the stream was used by travelers or pilgrims to wash their feet. Another links the name to the area of Nea Ionia, which, before the arrival of refugees following the 1922 catastrophe, was known as Podaradika, a name that may have inspired the term Podoniftis

A visit worth the effort

For those who want to experience this hidden gem, the easiest way is to take the metro to Ano Patisia station and then walk west along Chalkidos Street (see map below). After a few hundred meters, a world of greenery, birdsong, and flowing water opens up — a gentle reminder of nature’s presence in the heart of the city.

Podoniftis is more than just a waterway; it is a living witness to the history of Attica and a symbol of nature’s resilience. Preserving and valuing this natural resource is essential for the ecological and cultural future of the entire region.

Getting there

Sources

• https://gexynet.com/the-stream-of-podoniftis/
• Wikipedia podoniftis
• ‘https://greektraveltellers.com/blog/the-buried-rivers-of-athens
• https://greektraveltellers.com/blog/the-buried-rivers-of-athens