One of the really unique and interesting things about the downtown campus is the "subway" under the streets. If it is 30 below zero, or over 100 you can move around to different buildings, shops, and even hotels you can be comfortable walking, or being pushed. The Clinic is 18 stories and cover most of a city block. For the size of the city.... 114,000 Mayo employs about 33,000..... they do almost 1300 blood draws a day.