The Haram-e Razavi is the centrepiece of Mashhad and one of the holiest sites in Shia Islam, drawing more than twenty million pilgrims a year. The complex covers some six hundred thousand square metres of porticos, courtyards, prayer halls, libraries, and the central golden-domed mausoleum of Imam Reza itself. The scale only becomes obvious once you are inside: courtyard opens onto courtyard, each one larger than the last, each one with its own ringing tilework and crowd-handling rhythm.
Non-Muslim visitors are welcome in most of the outer courtyards (you can usually arrange a free, official, English-speaking guide at the international visitor office near the entrance), but the inner sanctum around the tomb is reserved for Muslims. Dress is conservative — men in long sleeves and trousers, women in chador, which is provided at the gate. Allow several hours; come once during the day for the tilework, and again after dark for the lights and the atmosphere.