Undoubtedly the top attraction in Bethlehem, a veritable citadel built fortress-like on top of the cave where Jesus was born to Mary. It is one of the oldest churches in the world, and has been inscribed on the UNESCO World Heritage List. The first incarnation of the building was erected on the orders of the Roman Emperor Constantine I (the Great) in 330 CE. While the layout largely corresponds to Emperor Justinian's plans from 540 CE (the first building having been destroyed in a 536 riot), the church was first heavily fortified by the Crusaders and then degraded (mostly through neglect) under Mamluk rule. An earthquake in 1834 and a fire in 1869 didn't help. Today, the structure is mostly sound but somewhat dark and gloomy in appearance, only the adjoining Franciscan Church of St Catherine (dated 1881 and the site of the yearly December 24 midnight mass broadcast around the world) being in excellent shape. The alleged site of Jesus' birth is actually in an cave in the church (the original Manger where Jesus was born was a cave, not a shed, as popularly depicted). There is a star marking the exact location of Jesus' birth in the cave. The original Manger with the star marking Jesus' birth site is called the Grotto of the Nativity, and is accessible from inside the church. (The tomb of famed theologian and Bethlehem resident St. Jerome, who spent his life translating the Bible, is also in the cave with the Grotto.) Entrance to the entire complex is free, but in the high season (and especially on Jan 6th) be prepared for massive crowds and hour-long waits for entry into the Grotto. There are usually accredited but dodgy tour-guides waiting at the entrance or inside of the church who offer to give tours to groups/individuals, sometimes allowing you to skip the crowds. Makes sure to agree on a price before taking the tour, and if the promise was to skip the crowds and get into the crotto directly but not possible sometimes, lower the price by at least half. Otherwise do not support them, as it is unfair to the other visitors waiting.