There are a few mosques in Lanzhou, but this one's the biggest. Originally built during the Wanli Period of the Ming Dynasty, the current mosque is a 1990 rebuild. Definitely one of the must-see sites in Lanzhou.

I visited Xiguan Mosque in December 2020. This mosque is large and imposing looking. It is centrally located in Lanzhou’s CBD and bounded by Baiyin, Cuiyingmen and Linxia Roads. The site has considerable historical significance as the first mosque was built here in the reign of the Ming Emperor, Yongle (reigned 1402-1424). It was extended and somewhat rebuilt during the Qing Dynasty, and then demolished during the early 1980s, and built anew in 1990. It has been built adjacent to the former Ming Xuichuan Gate (also demolished). The Xiguan Mosque has four tall minarets and a central dome in the traditional Arabic style, and appears to have many Chinese architectural motifs along the exterior walls. I did not expect to enter the mosque as I am not a Muslim and my Chinese is not well developed. I am not sure whether having a Muslim Chinese guide might help gain access for the purpose of self-education. As a tourist here for one week, I found this too difficult. Unfortunately, the mosque is surrounded by major roads, a flyover expressway with roundabouts, and high rise buildings. Even the front is obscured by a massive digital screen. I guess this is my opinion though as a tourist and I am sure it is not shared by local Muslims. Having said that, I think it is well worth the visit to appreciate such a holy place of worship. It is quite beautiful at sunset and at night with considerable decorative lighting. Perhaps include it on a walking expedition to other nearby attractions to avoid disappointment. I was told by a young Muslim scholar that for Lanzhou Muslims, this is a very special mosque, a very special meeting place and a destination for large numbers of foreign Muslims who visit the mosque each year for study and for worship.