The Titus Tunnel (Titüs Tüneli) is a Roman engineering marvel.
They put Roman legionnaires, sailors and prisoners to work cutting a channel along and through the rock for about 1.4 km (nearly a mile).
Continued under Emperor Titus (79-81), inscriptions tell us it was completed during the reigns of the Antonine emperors decades later.
Today the channel is dry, but still worth a visit. A small parking area and entrance is just inland from the beach at Samandağ. A path ascends along the channel, open to the sky, up and down steps and rocks, to where an arched limestone footbridge crosses.
Above the footbridge, the channel continues into the solid rock. You'll need a powerful flashlight/torch to continue.
—by Tom Brosnahan