Ghadames
Ghadames, an old oasis city, is located on the Libyan border with Algeria and Tunisia. The old town is a maze of tunnels, residences, courtyards, and places of worship built underground to avoid the heat of the Sahara. It is considered one of the most beautiful historical sites in Libya you should visit.
Several houses in the abandoned town have been furnished and renovated to offer the few visitors an impression of what it was like to live there. You can also travel across the rooftops like the native women used to, although this can require some really perilous crossings — not for the faint of heart.
In 1986, UNESCO designated the Old Town of Ghadames as a World Heritage Site. It is threatened by destruction and decay as a result of the adjacent Libyan Civil War, and was thus added to the List of World Heritage in Danger in 2016.