Lake Baikal, situated in Siberia, is the largest and deepest lake on earth. It contains enough water to cover the whole globe in 20 cm of water. We want to be the first to cross this lake in the 700 km longitudinal direction solely on foot. We will walk on a 70 to 120 cm thick layer of ice. The best method to transport our baggage under these conditions is to use a special sled called a pulka. In this way both of us can eachpull 80 to 100 kg of equipment, clothing and food. The mean calculated expedition time is about 6 weeks, but we have scheduled another 2 weeks just to be on the safe side. Most people do not really understand why some people do such things voluntarily. There are several reasons.