Crossing the Mekong river near Champasak, one sees the mountain called "Lingaparvata," so named because the natural formation (top of mountain, center of photo) seems to resemble Shiva's linga. To many visitors, it even more closely resembles a female breast. Wat Phu nestles at the base of this mountain, which has been a sacred site from at least the 5th century A.D., being associated with the early kings of Chenla.
"Parvata" means "mountain," so "Lingaparvata" is literally "Linga Mountain." It is the same word-root as "Parvati," the name of Shiva's consort, a mountain-goddess.