Odesa's Catacombs: A City Carved Out From Under Its Own Feet

Take a walk along a boulevard in Odesa, the port city on the Black Sea. Twenty metres under your shoes, there is black rock and total silence. Not a cellar. Not a metro line. Thousands of kilometres of tunnels, and to this day nobody has a full map of them. No other city on the planet has more emptiness beneath it.

Your first guess is probably the same as anyone's: nature. Water ate through soft stone for millions of years, the way it does in mountain caves. It's a nice theory. But these corridors have right angles. The walls are straight. And on them run parallel grooves from a saw, neat as lines in a school notebook. Water can't do that.

Everything here was cut by hand. The stone is a shell rock, a Pontic limestone made of pressed-together mollusc shells. It lay on the bed of an ancient sea about six million years ago, and then that seabed became dry land. It's a remarkable material. Soft enough to cut with an ordinary handsaw, and strong enough that a house built from it stands for centuries. The saw goes in easily and the block comes out finished. Cut it, lay it.

Then comes the almost absurd part. The city needs stone, so it takes the stone from right under the future street. Cut a block, and you leave a hole. Those blocks became the yellow city above the sea: the mansions, the staircases, the port. Odesa built itself out of what it lifted from under its own feet. Every handsome façade up top is one missing piece of ground down below.

The bill came due in the nineteenth century, when people built fast and hungry. They dug in small crews, in every direction, each under their own plot. Nobody kept a common plan. So what you get is a maze, on three levels, in places more than fifty metres deep, stretching along the coast for almost a hundred kilometres.

Then the buildings started to crack and sink. By the end of the twentieth century, around forty percent of the old town stood over undermined ground. In the nineteen-eighties alone, surveyors counted two hundred seventy-six serious deformations in buildings, and three dozen houses people lived in had to be pulled down completely.

The fix goes like this. Crews drill a shaft and pump a mix of sand and water down it under pressure. The slurry fills the void and sets, and the foundation rests on solid ground again. In a year and a half, this brought support back under sixteen buildings in the historic centre.

And then something happened that the quarrymen never expected. Pushing through yet another tunnel, they would break into a cavity with uneven walls, mineral drip and gypsum crystals. A real karst cave. The kind that water really did carve, millions of years before any human showed up.

And these caves held the real find. They were packed with red-brown clay, and in the clay, bones. A great many bones. The ancient animals of a time when dry steppe lay where the streets are now: camels, hyenas, ostriches. In nineteen sixty-three, Odesa scientists set up a reserve on one such site. It's a rare case where what is protected is not the cave, but what it's stuffed with.

Down there, the air is its own climate. Twelve to fourteen degrees Celsius all year round, and humidity close to a hundred percent. So for centuries people used these tunnels as storerooms, wine cellars and shelter. People hid here in wartime, and a museum in the village of Nerubayske tells that story. People stored wine here, and distilled home-made spirits. And up on the surface, tree roots push through the rock, looking for water.

So how long is it all? About two and a half thousand kilometres. That's roughly a flight across the whole of Europe, laid out underground. But it's an estimate, made at the end of the nineteen-nineties, and no more than that. A large part is flooded, and part was filled in on purpose so it wouldn't collapse. New passages are still being found. For decades, clubs of cave explorers have measured the maze, metre by metre, with a tape and a piece of chalk.

What you get is a strange symmetry. Above, the city you can see. Below, its negative, an empty reflection of the same shape. And that reflection still has no complete map.

Anything at all — a building, a word, a habit you never questioned. moygid dot online.