The bus tour, taking place Saturday, September 15, focuses on transportation developments of Colorado's past as well as plans for the immediate future. Participants in the half-day trek will go from Union Station to Stapleton to Denver International Airport and back. The architectural emphasis will begin with a discussion of Union Station's original framework, and the current Landmark Association-approved expansion of the urban hub, over an 8:30 a.m. brunch in the station."I think past ideas around transportation are so formative for our city, and with that comes a message of preservation," says Ann Levinsky, Director of Historic Denver. The Stapleton stop will focus on a viewing of Hangar 61, one of the defunct airport's original hangars used to house the Boettcher family's private plane. Built in 1959, the structure has now been adapted for use as a church.