Our relatives brought us to visit this temple on a hill top.
Wat Phnom is the only hill in town. According to legend, the first pagoda on this site was erected in 1373 to house four statues of Buddha deposited here by the waters of the Mekong and discovered by a woman name Penh. The main entrance to Wat Phnom is via the grand eastern staircase, which is guarded by lions and naga (snake) balustrades. You can read more from source.
We need to pay US$1 to visit the temple while the locals visit for free.