 At that time some of the world's earliest skyscrapers were constructed in the area, starting a legacy of architecture in the area that continues to this day.In the late 19th century cable car turnarounds and a prominent elevated railway loop encircled the area, giving the Loop its name.Starting in the 1920s many highways were constructed in the Loop, most prominently U.S. Route 66, which opened in 1926 with its eastern terminus in the area.