Bird's nest hotel (Swiflet hotel)

People here use old buildings, or even custom build "hotels" to house swallows (swifts) where the birds live and build their nests. These nests, which are stuck together using the saliva of the bird, are harvested and sold for thousands of dollars per kilo. They are then cooked into fthe highly expensive and luxury dish of Chinese Birds' Nest Soup. As the product is so valuable, the 'hotels" are razor wired and guarded.