A small 8th-century Umayyad bathhouse, unremarkable from the outside, that hides one of the most important surviving collections of early Islamic figurative art anywhere — hunting scenes, musicians, a zodiac ceiling, and a rare nude bathing fresco, all UNESCO-listed. It's one stop on the wider Desert Castles loop east of Amman, usually visited alongside Azraq and Qasr Al-Kharrana.
Qusir Amra is about 85 km (75-90 minutes) east of Amman on the Desert Castles loop, roughly 25 minutes from Azraq.
Spring and autumn, for the drive and the walk between the desert castle sites — the exposed eastern desert is genuinely rough in summer heat with no shade along the way.
Don't rush past this one — from outside it looks like a plain stone building, but the frescoes inside are the actual reason it's UNESCO-listed. Photography of the frescoes may be restricted to protect the pigments, so ask on-site rather than assuming.