dangerousroads.org

Y7PlW TIL that Canada's Dempster Highway, the only public road to cross the Arctic Circle, once had a 109-mile stretch called Tuktoyaktuk Winter Road. Tuktoyaktuk Winter Road was purely made of ice and could only be operated, especially by large trucks, during the winter as the river below was frozen.
9wdl6 TIL at 4752m (15,590ft), Mila Mountain Tunnel in Tibet, China is the highest vehicular road tunnel in the world.
rN90o TIL the longest traffic jam in history lasted for 12 days. It occurred in China in 2010 on the Beijing-Tibet Expressway and stretched for over 62 miles (100km).