The ancient town of Myra in Turkey may sound familiar to you, because St. Nicholas was the bishop of Myra. Another claim to fame for the region is the many ancient ruins one can see there.
Perhaps most striking of all the ancient ruins in Myra are the rock-cut tombs of the ancient Lycian necropolis. Two burial sites, the river necropolis and ocean necropolis, with frontages resembling classical temples, are hewn from the cliffs towering above the town.
You can imagine the years of work that went into carving these tombs out of the cliff faces. See plenty of pictures of them at Urban Ghosts. Link
(Image credit: Flickr user Caleb Maclennan)