Chicago’s Fulton Market Cold Storage Company was housed in a 10-story building in the meatpacking district for 90 years until last July, when they decided to move to a warehouse in the suburbs. The building was sold to bike component manufacturer SRAM to be converted into their world headquarters. Architects Perkins + Will were tasked with turning the ice-encrusted building into a modern machine shop, workspace, and indoor cycling track for SRAM. What ensued was one of the most epic building defrosts in history. Fortunately talented professional photographer Gary Jensen was there to snap some amazing before shots, a sampling of which are below. Head to his site for the whole mesmerizing set. The thawing was also documented in this timelapse video, spanning from 7 p.m. on November 8 to around noon on November 13. You get a flash of the large propane heaters they brought in to speed things up at the 24 second mark.