زمزم
The "Masjid al-Haram" is the largest mosque in the world and the most expensive single building in the entire world, valued at 100 billion US dollars, as of 2020. It is the site of two of the most important rites of both the Hajj and of the Umrah, the circumambulation around the Ka'bah ("tawaf") and the walking between the two mounts of Safa and Marwa ("sa'ee"). The masjid is also the site of the Zamzam Well. According to Islamic tradition, a prayer in the masjid is equal to 100,000 prayers in any other masjid around the world.