Mashhad is home to the magnificent Imam Reza Shrine, one of the holiest sites in Shia Islam and the world's largest mosque complex by dimension. The city serves as a major pilgrimage destination, attracting millions of Muslim visitors annually who come to pay respects to Imam Ali al-Ridha, the eighth Shia Imam. The shrine complex showcases exquisite Islamic architecture with golden domes, intricate tilework, and calligraphy, representing centuries of Islamic artistic heritage.