On authority of Shaikh Toosi from Imam Reza (as) said: In Khurasan there will be a Shrine and a time will come that Shrine will be a place of visit and Tawaf of angels until the day of Qiyamat, He was asked which Shrine is that? He said it will be in the land of Toos (Mashhad Iran) by the name of Allah swt it is one of the garden of the gardens of the Heaven, if any one visits me there its as he has visited the Holy Prophet (sw) and will be rewarded equals of rewards of 1000 acceptable Hajj and 1000 acceptable Umrah, and I and all my ancestors will intercede his sins.
In other narration Bazanti says: I read a letter from Imam Reza (as) was written; Say to my shia my Ziyarat is equal to 1000 Hajj, I asked Imam Jawad (as) surprisingly, equal to 1000 Hajj? He said yes if someone visits Him knowing his position will be rewarded equal to one million Hajj.
(Ref: Man La Yahzuruhu Al-Faqih Vol2 p349, Al-Tahzib Vol6 p85)