While the construction of the 1893 World's Fair took place in Jackson Park, most of the planning took place on the 11th floor of the Rookery building. Daniel Burnham built the Rookery 2 years before he was named the master architect of the fair, and his offices here served as the meeting place for many of the great minds who helped to shape the exposition. If you can, peek into the library, which will transport you back in time, and try to imagine what the city looked like back when this vantage point had unobstructed views of the lake.