The various sports activities that can be practiced on the icy surface of a lake, from hiking to snowmobiling, require an appropriate ice thickness. A 3.9 in (10 cm) thick ice would support a weight of about 198 lbs (90 kg), allowing the passage of a hiker or a cross-country skier. On the other hand, it would take 4.7 in (12 cm) of ice to circulate with a snowmobile of about 793 lbs (360 kg) and between 7.8 and 11.8 in (20 and 30 cm) to support the weight of a car or a group of walkers. Beyond 11.8 in (30 cm), it is even theoretically possible to cross a body of frozen water in a 4X4 or a van.