Kostivere karst area reveals its changing underground river

The Kostivere karst area is currently offering visitors a chance to walk among limestone formations before rising water covers them, ERR reports. A new educational trail there will also be accessible to wheelchair users.

Local nature guide Tiia Nool said the underground Jõelähtme River is beginning to push back to the surface. The water level can fluctuate by as much as five metres, she said, so the landscape can look very different after heavy rain, when the underground river can no longer carry all the water.

For now, the water has receded, leaving the formations known as stone mushrooms and residual cliffs exposed. Visitor Anna said she had come to see the natural spectacle and was surprised to find that “you can walk on the river”.

Nool warned that the limestone riverbeds can sound hollow underfoot as water moves below and above them, wearing away the rock. Some places could give way, dropping a visitor into the water.

Visitors on Tuesday were not worried about falling through, but RMK, which is building the new educational trail, plans to guide people away from dangerous spots. A wheelchair-accessible boardwalk is due to be completed in the coming weeks, with the final solution expected by next spring.