Within less than one square kilometer of Ottoman-era walls, Jerusalem's Old City contains sites sacred to Judaism, Christianity, and Islam — a concentration of spiritual significance unmatched anywhere on earth. The four quarters each have their own character: the Jewish Quarter rebuilt after 1967 around the Western Wall plaza, the Muslim Quarter's bustling souks and the approach to the Dome of the Rock and Al-Aqsa Mosque on the Temple Mount, the Christian Quarter centered on the Church of the Holy Sepulchre where pilgrims trace the Via Dolorosa, and the quieter Armenian Quarter with its ancient monastery. The density is overwhelming — turn a corner and you shift between centuries and civilizations. Come early morning to beat crowds at the major sites. The rooftop walks along the ramparts offer perspective on how impossibly compact this contested, layered, sacred city really is.