That decision proved to be beneficial in overcoming the Midland's lead and bringing the first train to Aspen in October 1887. At that point the Midland's crews had laid track almost as far as Maroon Creek. The railroad had hired renowned engineer and bridge designer George S. Morison to design and build the viaduct using his innovative double-bent piers, first used on the Portage Viaduct in New York and later on the Boone Viaduct in Iowa. A timber trestle could have been built, but when the crews reached the creek in December they had to wait as the structural steel for Morison's bridge had been delayed leaving its fabricator back East. They continued working through the difficult mountain winter and completed the bridge in time for the Midland's first train to cross it and arrive in Aspen in February 1888. Although the Midland lost the race, its bridge, one of the last viaduct bridges built in Colorado that century, was more significant since it connected Aspen to its standard-gauge main line, the first built into the state's mountains. In 1890 the Rio Grande widened its branch to standard gauge. The two railroads competed vigorously as the city's population swelled to over 10,000. The Aspen City Railway, a mule-pulled streetcar, connected the two depots.