Speleologists started on a discovery expedition to Odessa Catacombs

Odessa speleologists will spend 5 days underground in catacombs which are considered to be the most extensive and most twisted in the world. The task of the team is to explore the labyrinths and map the dangerous zones for rescue activities and construction works. For three days speleologists explored only 20 kilometers which is the hundredth part of the underground labyrinths.

Millions years ago here was the seabed, so this limestone (shell rock) territory was mined out in XIX century to quarry stone for building the city. Almost all buildings in the central city from Deribasovskaya Street to Privoz are built from limestone quarried underground, so Odessa is called the "Inside-Out City". The problem is that limestone gets wet, it is pressed down and Odessa might go down into the Black See some day.