"The Sacred Mosque"

The Grand Mosque in Mecca city.

Al-Masjid al Harām "The Sacred Mosque"), is the largest mosque in the world. Located in the city of Mecca, it surrounds the Kaaba, the place which Muslims turn towards while offering daily prayers and is considered to be the holiest place on Earth by Muslims. The mosque is also commonly known as the Haram or Haram Sharif.The current structure covers an area of 356,800 square meters including the outdoor and indoor praying spaces and can accommodate up to 4 million worshippers during the Hajj period

source: wikipedia