Muhammad's tomb is located under the Green Dome of Al-Masjid an-Nabawi.

Medina (/mɛˈdiːnə/; Arabic: اَلْمَدِينَة اَلْمَنَوَّرَة‎, al-Madīnah al-Munawwarah, “the radiant city” (officially), or اَلْمَدِينَة al-Madīnah), also officially transliterated as Madinah on Saudi maps and in modern Islamic literature generally, is a modern city in the Hejaz region of western Saudi Arabia, and serves as the capital of Al Madinah Province. An alternative name is Madinat Al-Nabi ("The City of the Prophet," i.e. Muhammad). The Arabic word madinah simply means "city." Before the advent of Islam, the city was known as Yathrib but was personally renamed by Muhammad.

• http://en.wikipedia.org/wiki/Medina
• Hillman 1000 Wonders