Two places are considered the holiest places in Islam. One is a place called “Kaaba” which is in the centre of city of Mecca in Saudi Arabia. Kaaba is the name of a cubical structure which commemorates the first house of worship built by prophet Adam and then rebuilt by prophet Abraham. Prophet Muhammad(sa) was born close to this place and early history of Islam revolves around this place and the city of Mecca which was an important trade route as well. Muslims perform pilgrimage every year by visiting Kaaba and Mecca and trace the history by walking through the footsteps of Ishmaeel and his mother Hajira, wife of Abraham. Amazing how the roots of Islam go to Abraham, the patriarch.
The second holiest place is considered the city of Medina about 200 km from Mecca. This is the place where prophet Muhammad(sa) migrated after his persecution in Mecca and established a community of Muslims and the famous mosque, the mosque of prophet was built from mud. Now this mosque is a beautiful place to visit. Prophet Muhammad(sa) and many of his family members are buried there as well.