Tlos is one of the oldest and most important cites in ancient Lycia, and its position atop a rocky outpost dominates the Xanthos Valley. Hittite artifacts found here indicate the city was founded as early as 2000 B.C. After the decline of the Hittite Empire, Tlos became a Lycian city, and then was later absorbed by the Roman Empire. The city was an important bishopric during the Byzantine Era and was finally conquered by the Turks.

The most immediately impressive feature is the severe slope of the city on the rock, carved into majestic temple-like tombs, and the stone sarcophagi dotting the hillside below. A lone sarcophagus sits dramatically in the middle of a farmer's field best spotted from the stadium, located a few hundred feet up the road of the ruins near a roadside cafe graced with ice-cold springs. Take a look at the stadium first, because after the climb to the summit, it will be too much of a struggle against the heat to tack this on to the end of your tour. On the summit lie the ruins of a castle dating to the Turkish settlement, offering panoramic views of the Xanthos Valley. Excavations conducted by Antalya University have uncovered a tunnel, which seems to have provided a quick escape during times of invasion, leading to the city from the nearby village.