This September, Cincinnati will debut its new streetcar. The 3.6-mile-long system will run a loop through downtown and the city’s Over-the-Rhine neighborhood. It will be the first time streetcars have carried passengers in Cincinnati since 1951. At one time, the city had a streetcar system that ran over 200 miles and carried 100 million passengers a year at its peak. Built to accommodate a growing population in the mid-19th century, the electric system ran smoothly but for one problem: It didn’t have enough power to get up and down the city’s hills. The solution was four cable-operated inclined railways that worked like elevators. Streetcars drove onto a platform and were simply carried up and down the hills. Today, the inclines are long gone. All that remains are some stone piers and steps. Ideas for what to do with the ruins have been batted around, including converting them into a park with a serpentine walking path or building an aerial gondola.