The most important factor that has been effective in the formation of Mashhad's current location throughout history is the natural location of the Kashf River basin and Atrak River. By considering this factor as a relatively constant thing to attract the population, the influence of historical, political, social, and religious factors can be investigated in different periods. Kashfroud river basin was one of the major centers of settlement in North Khorasan during the entire Islamic period and even in the pre-Islamic period. In the Islamic period, the most important and most populated settlement was the Kashf river basin of Tus province, the center of which was the city of Tabran. Over time, the importance of the cities of Tabran and Neishabur decreased and new settlements named Noghan and Senabad grew. Sanabad is located 2 kilometers from Nuqan. After a few years of his caliphate, Harun's successor, Ma'mun, as a result of the rebellion that arose against him in Iraq, to win the favor of the Shiites, nominated Hazrat Reza (a.s.) Did Hazrat Reza (a.s.) leave for Baghdad after staying in Marv for a year, when they reached Nughan village, he entered Manzamir Sanabad, where he was poisoned and died in 202 or 203 AH after three days. His body was buried in Hamid Bagh. Bin Qahtaba was buried 1.5 km from the village of Senabad, since then the mentioned place has been called Mashhad al-Reza and then Mashhad in short.
Mashhad is a metropolis in northeast Iran and the capital of Razavi Khorasan province. It was the capital of Iran during the Afsharian dynasty. According to the general population and housing census of 1395 AH, with a population of 3,057,679, it is the second most populous city in Iran after Tehran.
Mashhad receives millions of pilgrims from inside and outside the country due to the presence of the Noorani Court of Hazrat Ali bin Musa al-Reza, peace be upon him, a wide range of facilities including an active international airport with numerous domestic and foreign flights, a modern terminal and a suburban transportation network. Within the city, the most active train station, the existence of highways and suitable roads, the largest number of hotels and guesthouses in the country, and the existence of natural and historical attractions and tourism attract more and more citizens to this city every year.
In addition, the presence of consulates of many Muslim countries in Mashhad shows the wide range of political-economic relations of those countries with Khorasan Razavi province and Mashhad city, and their Shiites make up a significant number of Mashhad pilgrims. The attractions and facilities of Mashhad have also increased the population and development of Mashhad so the population of this city has increased more than 3 times compared to 1355.