Sage Green — 13 museum-grade prints in this palette. Petra was the capital of the Nabataean kingdom from roughly the fourth century BCE, a caravan city carved into rose-red sandstone cliffs in southern Jordan. Al-Khazneh — the Treasury — is the most photographed facade, though scholars debate whether it served as a royal tomb or temple. Paro Taktsang — the Tiger's Nest — is Bhutan's best-known monastery, built around a cave associated with Guru Rinpoche and reached by a trail that climbs roughly 900 metres from the valley floor. Lungta prayer flags carry mantras and blessings on the wind in Tibetan Buddhist tradition; the five colours represent sky, air, fire, water, and earth. Chefchaouen earned its Blue Pearl nickname from medina walls washed in shades from powder to cobalt — a tradition linked variously to Jewish refugee communities, pest-repellent folklore, and the simple fact that blue photographs beautifully against Rif Mountain light. The old town's Plaza Uta el-Hammam and the Spanish Mosque viewpoint draw millions of travellers annually, but travel-poster artists from Art Deco lithographers to contemporary print sellers return to the same essentials: stacked blue facades, mountain backdrop, and the archways that frame countless doorways.