There are lots of Muslims in Lanzhou, and Gansu in general. Mosques are everywhere. They are easy enough to spot with their distinctive onion-shaped domes and minarets. I understand they used to make the calls for prayers on top of the minarets. But when I heard the call for prayers around noon in Lanzhou, I could not really see anyone calling from the top of the minarets. Perhaps they use loud speakers these days.
This one is squeezed between the Yellow River and the mountains. Lanzhou is one long city on both sides of the Yellow River, hemmed in on both sides by mountains. At some places it is really narrow, as evident in this picture.
Most Muslims there are Hui (回族), with a small number of Dong Xiang (東鄉族). Many of the men wear white skull caps. The young do not look too different from the Han (漢族)。 The older folks can look rather distinguished, with their white skulls caps, long white beards and weathered faces.
Hence it is easy to find beef and particularly lamb in Gansu. But not pork.
We went looking for Lanzhou lamian (pulled noodles) 蘭州拉麵. This is the kitchen of one of the most famous noodle shops in Lanzhou. For 20 dollars you get a set of four bowls of noodles, with assorted meats. From fine noodles to thick to triangular (in cross-section) to as wide as a belt (the whole bowl consists of one long belt). Plenty enough even for me.
It turns out the local custom is to eat beef noodles mainly for breakfast. In early morning on our last day in Lanzhou, we went for noodle breakfast. For three dollars we got a big bowl of noodles and just a few mossels of meat. For three extra dollars we got several slices of meat. Very tasty, very good, chewy noodles. We were satisfied.