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Fun video. The animal park looks like a blast. There is an old "trench" in Minneapolis also. It used to have tracks but they removed them and it's now a bike path called the Midtown Greenway. https://midtowngreenway.org/about-the-greenway/
Also in NYC there is a park called The High Line that was created on a former elevated railway. I've walked it, it's a neat place to visit. The trail goes through a few buildings even.