At 1,300 km (807.7 mi) long, Karakoram Highway is considered the
world’s most high-altitude international highway. One of its sections
passes at an altitude of more than 4,600 m (15,091 ft). Summer monsoon
rains often wash it out and cause landslides. In winter, the highway
is closed due to weather conditions and possible avalanches.
[8] Passage du Gois, France
This seemingly common passage connects the island of Noirmoutier with
mainland France. However, during the tides, it’s fully covered with a 4-m (13 ft)
layer of water and is available to drivers only twice a day.