It's not going to give you much of a "canyon" experience. The parking lot is at the bottom and the path is heavily wooded. You'd be hard pressed to realize you are in a canyon while walking around. I grew up in Arlington and moved back when I had a kid to raise. I've always though of the spot as more bottom of a hill than canyon. It is a great little nature walk though.
It's more like small walk
Not sure of actual feet, but it's not a deep canyon, probably 30-50 feet at deepest point.
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