First, Mecca, the holiest site in Islam. "Mecca is the holiest site in Islam, and millions of Muslim pilgrims come here every year to complete the Hajin prayer. "Islam stipulates five basic religious obligations, known as the Five Gongs, which are: recitation, ritual, fasting, teaching, and pilgrimage. Hajj means that a Muslim who is able to afford it makes the Hajj pilgrimage to Mecca at least once in his lifetime during the prescribed Hajj period. 
The whole of Mecca was built around this mosque. ）
Mecca is the birthplace and founding place of the Prophet Muhammad. The Prophet Muhammad was born in Mecca and founded Islam in 610 A.D. on a night in the month of Ramadan in the cave of Hira in Mecca. The Prophet served as a missionary in Mecca for 12 years, and then was opposed by the Meccan elite and left Medina. After Muhammad established power in Medina, he led his army to conquer Mecca after 630 AD, abandoned polytheism, and converted the Ka'ba temple into an Islamic mosque. 
For more than 1,000 years, with the increasing development of transportation, the number of Muslims visiting Mecca for Hajj has increased year by year. In 2023, about 2 million Muslims from 160 countries arrived in the holy city of Mecca for the Hajj. 
The Grand Mosque of Mecca after three rounds of expansion. ）Second, Medina, the second holiest site in Islam. The Prophet established the first Islamic regime in Medina.
In 622 AD, the Prophet Muhammad was forced to migrate to Medina and founded the first new Islamic city on earth, which was renamed Medina-Nabinyi, which means "City of the Prophets". The first Islamic regime (Umah) was established here, and Medina became the first capital of a Muslim state. 
Mecca is the birthplace of Islam, then Medina is the first step of Islam to the world, because in Medina, the Prophet began to spread Islam to people of different faiths and different nationalities. It has been parabled that Mecca is the heart of Islam, that the revelation of Allah was first revealed under the auspicious Ka'bai, and that Medina is the body of Islamic civilization, where Allah sent His Messenger to successfully practice the spirit of Islam for the first time. The Prophet died in Medina in 632 due to illness in 632 and was buried in Medina. 
3. Jerusalem, the third holiest site in Islam. Jerusalem is made up of the roots of jeru (city) and salem (peace), which means "city of peace". Jerusalem is also the holy site of the three Abrahamic religions of Judaism, ** and Islam (or the "Three Revealed Religions"). 
The history of Jerusalem dates back to the fourth millennium BC. Around 2000 B.C., Judaism was born, about the 1st century of the Convention, Islam was founded by the Prophet Muhammad in 610, Judaism, ** Christianity and Islam have a common source - ancient Judaism. Religion is a branch of ancient Judaism, while Islam has absorbed some of the teachings of Judaism and Islam. All three religions are monotheistic and believe that there is only one God (Allah). Jerusalem is the holiest place in Judaism and religion and the third holiest place in Islam. 
The importance of Jerusalem to Muslims is manifested in three ways.
1. Jerusalem is the center of the three major monotheistic religions.
2. Jerusalem was the first place of worship for Muslims. The Islamic Prophet Muhammad led his followers out of Mecca and in September 622, 16 months after their migration to Medina, he was instructed by Allah to change the place of worship from Jerusalem to Mecca. 
3, Jerusalem shows the miracle of Allah in 620 Muhammad's night ascent to the sky (Muslims believe that Muhammad rode a heavenly horse from Mecca to the Temple Mount in Jerusalem in one night, ascended to heaven, and met Allah). Muslims believe that the stone on which Muhammad walked through the night was in the Dome of the Rock. 
Jerusalem Dome of the Rock) Jerusalem is of special importance to Jews, Muslims and followers, having endured trials and vicissitudes. The Assyrians, Babylonians, Persians, Greeks, Romans, Byzantines, Arabs, Crusaders, Mamluks, Turks, British, etc., all exercised their power as conquerors here for decades or centuries. 
Cathedral of the Resurrection in Jerusalem, where the tomb of Jesus lies. ）
To this day, Jerusalem remains unresolved. Judaism considers all of Palestine to be holed in the world, and Jerusalem is the holiest of holies. Although Jerusalem is only the third holiest site in Islam, Muslims will not give up, and the competition for Jerusalem is an important reason for the long-term Israeli-Arab conflict.