The iconic city of Petra in Jordan is carved almost entirely from sandstone, specifically the Umm Ishrin Sandstone and the Disi Sandstone formations. This sedimentary rock was formed millions of years ago when the area was covered by an ancient sea. What makes the stone in Petra so special in 2026 is its "Rose City" hue; the rock contains high levels of iron and manganese, which have oxidized over time to create vibrant swirls of red, pink, orange, and even purple. The stone is relatively soft, which allowed the Nabataeans over 2,000 years ago to carve intricate, monumental facades like the Treasury (Al-Khazneh) directly into the cliff faces. However, this softness also makes the site vulnerable to erosion from wind and rain, leading to ongoing 2026 conservation efforts to protect the delicate carvings from the very elements that created the stunning "rainbow" patterns in the stone.