Tlos is an ancient ruined Lycian hilltop citadel near the resort town of Kalkan in the Antalya Province of southern Turkey, some 4 kilometres northwest of Saklikent Gorge. Tlos is believed to be one of the most important religious Lycian cites and settlement on the site is said to begin more than 4,000 years ago.
It is one of the oldest and largest settlements of Lycia (known as 'Tlawa' in Lycian inscriptions) and was subsequently inhabited by Romans, Byzantines and eventually Ottoman Turks, making it one of few Lycian cities to be continually inhabited up until the 19th century.
Tlos lies on the east side of the Xanthos valley atop an rocky outcrop that slopes up from a plateau from a modern village, but ends on the west, north and northeast in almost perpendicular cliffs.
The influence of many cultures upon Tlos has resulted in a patchwork of structures dominated by an acropolis and fortress. On the slopes leading up to the acropolis are numerous Lycian sarcophagi and many house- and temple-type tombs cut into the face of the hill. One such is the Tomb of Bellerophon, a large temple-type tomb with an unfinished facade of four columns featuring a relief in its porch of the legendary hero Bellerophon riding his winged horse Pegasus. A carving of a lion or leopard is inside the tomb.