Which element was critical to addressing transportation gridlock in 1890s Chicago?

The construction of the Loop was a pivotal development in addressing transportation gridlock in 1890s Chicago. The Loop refers to the elevated train system that encircled the central business district, enabling efficient transit for thousands of commuters. This infrastructure innovation allowed for the seamless movement of people within the densely populated city area, reducing congestion on the streets below.

By providing an elevated rail option, the Loop helped alleviate the bottlenecks caused by horse-drawn carriages and early automobiles. It facilitated rapid transit across the city, particularly beneficial for workers commuting to and from the bustling downtown. As a concentrated hub of activity, the Loop was essential in managing the growing population's transportation needs during a time when urban growth was accelerating.

While other transportation elements like tram systems, suburban train extensions, and cycling routes contributed to the overall functionality of Chicago's transit network, the Loop specifically transformed the dynamics of downtown travel, thereby directly impacting the issue of gridlock in the 1890s.