The Berca Mud Volcanoes are a geological and botanical reservation located in the Berca commune in the Buzău County in Romania. Its most spectacular feature is the mud volcanoes, small volcano-shaped structures typically a few meters high caused by the eruption of mud and volcanic gases.As the gasses erupt from 3000 meters-deep towards the surface, through the underground layers of clay and water, they push up underground salty water and mud, so that they overflow through the mouths of the volcanoes, while the gas emerges as bubbles. The mud dries off at the surface, creating a relatively solid conical structure, resembling a real volcano. The mud expelled by them is cold, as it comes from inside the Earth's continental crust layers, and not from the mantle.
The reservation is unique in Romania. Elsewhere in Europe, similar phenomena can be observed in Italy (northern Apennines and Sicily), Ukraine (in the Kerch Peninsula), as well as Azerbaijan.
The reservation is unique in Europe, with similar phenomena being observed in Siberia and Australia. If you consider going to the Muddy Volcanoes, you can do it as one-day trip from Bucharest (it’s a three hours drive).The expelled mud is cold from the very beginning, as it comes from inside the Earth’s continental crust layers, and not from the mantle. The place stinks a little bit like sulfur, but it is not unbearable, and after a few minutes you won’t even notice the smell anymore. There are no dwellings in the proximity, so the area is very quiet. All you can hear are the birds singing and the blurbs of the small volcanoes.
The muddy clods of earth, colder than ice, gurgle and boil underground; then, through numerous opened mouths, scattered all over the valley, they bubble upwards, bursting out either at a very low or at a higher distance.The mud volcanoes create a strange lunar landscape, due to the absence of vegetation around the cones. Vegetation is scarce because the soil is very salty, an environmental condition in which few plants can survive. However, this kind of environment is good for some rare species of plants, such as Nitraria schoberi and Obione verrucifera.
The phenomenon can be observed on two separate locations near the Berca commune, dubbed the Little Mud Volcanoes and The Big Mud Volcanoes.