On the western side of the temple of Baphoun at Angkor Wat, there is a retaining wall fashioned into a 60 m long reclining Buddha. The project was undertaken in the 15th or 16th century, and its pretty hard to make it out. The shot below of the signage about the figure may help - somewhat. It's hard to see even when you are standing right in front of it
[NOTE: The guidebooks refer to Baphoun as the world's largest jigsaw puzzle. The temple was taken apart piece by piece to restore it and then the Cambodia civil war broke out. All the records were subsequently destroyed duing the Khmer Rouge years, leaving archaeologists with the task of figuring out where to put each of the 300,000 stones to reconstruct the temple.]