Stock Photo - The largest of the craters measures 110 meters in diameter and has a small lake (known as Kaali järv (Lake Kaali)) in it. Impact velocity was 10-20 km/s and mass 20-80 tons. At the altitude of 5-10 km the meteorite broke into pieces. The greatest of fragment produced the main crater with a diameter of 110 m and 22 m deep. 8 smaller craters with diameters from 12 to 40 m and depths varying from 1 to 4 m. The explosion that caused the craters is estimated to have happened 4000 ± 1000 years ago (Holocene). The power of the impact (greater than the Hiroshima bomb) burned forests within a radius of 6 km. It has been speculated that the event has played a part in the mythology of the region. It was known as a ´sacred lake´ and there is archaeological evidence that it was a place of offering for many centuries. The lake was surrounded by a wall during the early Iron Age, (600 B.C. to 100 A.D.) The length of the wall was about 470 meters, its width around 2.5 meters and its heigth to two meters. Finnish mythology also has stories that propably describe happenings of Kaali. In runes 47, 48 and 49 of Kalevala-epos there is one of these stories. Louhi the evil wizard steals the sun. She also steals fire from people so there is a total darkness. Ukko, the god of sky orders a new sun to be made from a sparkle. Virgin of the air starts to make a new sun, but sparkle drops from the sky and hits ground. Sparkle goes to a ´Aluen lake´, and causes its water to rise. Finnish heroes sees ball of fire falling somewhere ´behind the Neva river´, where Estonia is also located from Finnish point of view. Finnish heroes starts to sail that direction to seek fire. Finally they find fire from forest fire. According to a theory first proposed by Lennart Meri, it is possible that Saaremaa was the legendary Ultima Thule, first mentioned by ancient Greek geographer Pytheas, whereas the name ´Thule´ could have been connected to the Estonian language word tule (´(of) fire´) and the old folk poetry of Estonia, which depicts the birth of the crater lake in Kaali. Asteroid 4227 Kaali is named after it. Kaali is a small group of 9 meteor craters in Saaremaa, Estonia.