Phimeanakas, Hindu temple in Angkor complex, Siem Reap, Cambodia.

Phimeanakas is a three-tier pyramid temple inside the Royal Palace enclosure of Angkor Thom, north of Baphuon. Its square terraces are built of reddish-brown laterite blocks, with grey stone on the upper level, where rows of square window openings and a partly ruined gallery remain. Small carved lions stand at the corners and beside the steep central stairways.

The temple was commissioned at the end of the 10th century under King Rajendravarman II and later modified under King Suryavarman I. These construction phases mark the evolution of the site over time.

The temple's Khmer name, Prasat Phimean Akas, means 'celestial temple'; it was originally called 'Golden Horn Mountain'. Legend holds that a nine-headed naga spirit lived in the golden tower atop the pyramid, taking female form at night to lie with the king, while no queen dared enter. Zhou Daguan recorded this tale in 1297.

Access to the site is through shaded paths from the east, and the steep climb requires sturdy footwear. The location lies within the larger Angkor complex and is best explored with a guide familiar with the grounds.

Zhou Daguan, a Chinese envoy, described the temple's golden pinnacle in his account of 1297 CE. Legend held that the king spent the first watch of each night in the tower with a woman representing a Nāga; if she failed to appear, his days were numbered.