Africa's 'oldest' tunnel hidden in the mountains and now completely abandoned - The underground town where people live in tunnels surrounded by gems worth millions - Hidden World War II tunnels to open for public - PICTURED: Famous World War Two tunnels complex undergoes revamp to 'tell the stories of the people of Gibraltar' - Tunnels used by Iran-backed groups in eastern Syria exposed - Sophisticated smuggling tunnel found between US and Mexico - Take a final look inside the 1,500ft-deep underground tunnels that will soon be shut off to humans for 100,000 YEARS - Sabrina Ionescu and Napheesa Collier's odd post-game 4 interaction in the tunnels causes confusion - Underground tunnels were built in Lebanon to attack Israel, envoy says - The world's 10 longest tunnels - including three in the same country