group of eight meteorite craters on Saaremaa Island in the Baltic Sea, 12 miles (20 km) northeast of Kingisepp, Estonia. The largest is 333 feet (110 m) in diameter, with a rim 20–23 feet (6–7 m) above the surrounding land. Thought to be an explosion crater because of this high rim and uplifted surrounding strata, it holds a pond about 53 feet (16 m) deep. The other craters are dry and range from 40 to 143 feet (12 to 44 m) in diameter. In these small craters the dolomite bedrock was mechanically crushed into fragments by the force of the impact. Many small iron meteorite fragments and some meteoritic dust have been found in the area. Mollusk fossils in the fillings of the small craters indicate the craters are 4,000–5,000 years old.