Tugaske is a Martian impact crater, approximately 31 kilometres in diameter. According to a surface age map of Mars based on US Geological Survey data, the area around Tugaske is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago. The elevation around the rim averages about 6700 meters above zero altitude, and the deepest part of the crater floor, in the central pit, measures 5,100 meters above zero altitude. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On Mars large craters are named after deceased scientists, writers and others who have contributed to the lore of Mars. Small creaters (less than 60km) are named after small towns and villages.