Did You Know? Matka Canyon Hides One of the World's Five Deepest Underwater Caves
Just outside Skopje, a dammed river gorge holds Macedonia's oldest artificial lake, a cave system among the deepest on Earth, and butterflies found nowhere else in the world.
Just 17 kilometers southwest of Skopje, the Treska River carves a deep gorge through the rock — creating a space that feels more like some distant, hidden world than a destination within reach of a city bus. Matka Canyon is one of those places locals take for granted, while outside visitors can barely believe it's real.
Macedonia's Oldest Artificial Lake
Lake Matka isn't natural — it was created in 1938, when the Treska River was dammed at "Sv. Andreja," forming an artificial reservoir still used today for electricity generation and irrigation. That makes it the country's oldest artificial lake — decades on, and yet it looks so natural that most visitors never even consider it wasn't always there.
A Cave Among the World's Five Deepest
The canyon hides roughly ten caves, but one stands out — Vrelo Cave, whose underwater extension "Podvrelo" ranks among the five deepest underwater caves in the world, at over 203 meters deep. Almost paradoxically, the presence of stalactites underwater told speleologists that the cave once had no water in it at all — it only filled up after the Matka reservoir was built.
A Micro-Reserve of Biodiversity
Across just 5,000 hectares, Matka is home to over a thousand plant species (20% of them endemic or relict), 119 species of butterflies and 140 species of moths — 77 of them Balkan endemics, and 18 entirely new to science at the time of their discovery. The canyon also served as one of the region's main refuges for wildlife during the glacial period, which explains why so many relict species that vanished elsewhere long ago still survive here.
Beyond its nature, Matka is also home to several medieval monasteries and churches that earned it the nickname "little Mount Athos" — a combination few places on Earth can offer: a deep gorge, an underwater cave among the planet's deepest, endemic butterflies, and centuries-old spiritual architecture, all half an hour's drive from downtown Skopje.
🔵 The underwater Podvrelo cave ranks among the world's five deepest, at over 203 meters.
🔵 Matka is Macedonia's oldest artificial lake, created in 1938.
🔵 118 of the canyon's butterfly species are Balkan endemics, and 18 were entirely new to science.
🔵 The lake's water temperature stays a constant 7-9°C, even at the height of summer.
MKNews Hub · "Did You Know?" Series · Episode 6 · August 17, 2026