Grand Canyon Rim to Rim, (R2R), is a hike from the North or the South Rim to the opposite side. As the crow flies, that’s about 10 miles. According to the NPS however, on the hoof it’s 21 miles or 23.5 miles depending on your route.
The Tanner Trail is a Rim to River trail. If you are thinking of Rim to River and back as
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