Lake Baikal in Siberia Russia is frozen for 5-6 months every year. In the middle of the winter time, one can walk and cars can ride on the surface of the lake. The ice of this frozen lake is so clear, you can even see bubbles and other things inside this lake. Somewhat crescent shaped, it is in the southern Siberia area of Russia and in 1996 it was declared a UNESCO World Heritage Site.Lake Baikal is the oldest lake in the world. It is home to approximately 1,700 to 1,800 endemic plant and animal species," said Jennifer Castner ofPacific Environment's Russia program. Additionally, it holds 20 percent of the world's fresh water, due to the lake's depth, which is on average near 2,500 feet deep.