3. Turkmen-Uzbekistan barrier
Length: 1,056 miles
Turkmenistan’s dictator Saparmurat Niyazov decided in 2001 that country needs more to remember him by something important once he’s gone. As a lasting legacy, he constructed 1,056-mile fence between his country and Uzbekistan. His motives were to prevent illegal immigration and smuggling. Neither Turkmen nor Uzbeks were impressed.