The Suncor Oil Refinery in Commerce City was built around and in between the BNSF Brush Sub and the UP Greeley Sub. A pretty smart way to build it, actually, as it give the refinery access to two railroads for moving product. Of course, when the refinery was built, what is now the BNSF Brush Sub was actually the Chicago, Burlington, and Quincy (CB&Q) mainline to Denver from Chicago. Two mergers later (Burlington Northern, and then BNSF), and it is now the BNSF Brush Sub. The UP track, on the other hand, has been UP for all but 10 years of its life. It was originally built by the Denver Pacific Railway in 1870. Ten years later, in 1880, UP bought the Denver Pacific, gaining a direct line to Denver from Cheyenne.
In the shot here, a BNSF local sits on the Brush Sub (to the right) while a UP local sits on the Greeley Sub (to the left), both waiting their turn to cross the diamond where the two subdivisions intersect.
