PETRA, Jordan — President Barack Obama set aside the Middle East's tricky politics Saturday to marvel at the beauty of one of the region's most stunning sites, the fabled ancient city of Petra.

"This is pretty spectacular," he said, craning his neck to gaze up at the rock faces after emerging from a narrow pathway into a sun-splashed plaza in front of the grand Treasury. The soaring facade is considered the masterpiece of the ancient city carved into the rose-red stone by the Nabataeans more than 2,000 years ago.

Obama's turn as tourist capped a four-day visit to the Middle East that included stops in Israel and the West Bank, as well Jordan. The White House set low policy expectations for the trip, and the president was returning to Washington with few tangible achievements to show. Aides said his intention instead was to reassure the region's politicians and people — particularly in Israel — that he is committed to their security and prosperity.