Rongbuk is the highest monastery in the world. It has quite a beautiful backdrop featuring Mount Everest. I did not have time to go inside. The cost to enter was 40rmb but you are permitted to wander around outside or do the Kora at no cost. This of course is not the focus of travel to this area. In the past, when base camp was 200 meters further up, visitors would occasionally stop by on the way to Mount Everest camp. Now that base camp has been moved to a lower location, below Rongbuk, more people visit the monastery than have in the past.
My first visit in 2013 I was the only one visiting the monastery because the tents were so far away. It is an amazing view if you have clear weather. There is a large stupa to the right of the main entrance. This is often photographed because it lines up nicely with the Mount Everest in the background.
My second visit to Rongbuk saw great changes to the surrounding area but the monastery had not changed much at all. There were more monks and nuns around and many more Yaks but it is not clear if this is a direct result of the changes to where base camp is located. I highly recommend walking the Kora.
