Original: The tomb of Prophet Muhammad later became part of the mosque when it was expanded by the Umayyad Caliph Al-Walid I. Mount Uhud is a mountain north of Medina which was the site of the second battle between Muslim and Meccan forces.
Simplified: The tomb later became part of the mosque when it was expanded by the Umayyad Caliph Al-Walid I/O. The first mosque of Islam is also located in Medina.