This paper presents the structural analysis and constructional method for the stabilization and strengthening of the foundation of the two entrance gates in Holy Shrine of Imam Reza (PBUH). The holy shrine of Imam Reza (PBUH) is a great complex in the city of Mashhad in Iran. It was founded nearly 1000 years ago and has developed and become extensive through the times. There are several entrances and wide courts around the oldest section in the centre of the complex. Recently, the extension scopes of this complex, required excavation and construction in the basements near the two main gates, called Saat and Naghareh Khaneh Edifice. These activities, near the 400 years old edifices, needed special mobilization, like, monitoring the historical buildings and strengthening their foundations. A deep study was performed, which pursued two purposes. The first purpose was to strengthen the foundation of the buildings and the second was to make a tunnel through the foundation of the buildings because of some operational benefits for the client. At the first glance these two purposes, seemed contradictory, but finally, a new structural system for the foundation were designed and built, which was able to carry the superstructure loads to the ground while a wide tunnel was constructed as well. Special scheduled sequences of construction were prepared, which was flexible and sufficiently reliable so as to overcome any undesirable circumstances and obstacles. Monitoring the buildings behaviour during the constructional phase was conducted to assist the execution directions. This project was carried out successfully and it is in use.