I want to nominate "The Narrows" in Zion National Park. I hiked it top-to-bottom ~1999, and really want to go back. The "T-2-B" hike starts with a 1 1/2 hour commercial shuttle to a cattle ranch. Hiking is dry for several miles, then you wade right in. At least a third of the hike is in shallow water, but sometimes knee-deep. The scenery is fantastic. If you go late, the upper canyon has some great fall colors.

Maplink for the start and the end
Here's a good pdf map: Zion Narrows Map

Trail guides
Utah.com - "The Zion Narrows route is the most popular hike in Zion Park, and one of the world's best canyon hikes. It is pure fun and can be tailored to suit any ability level."

Joe's Guide to Zion - "The North Fork of the Virgin River (aka "The Zion Narrows") is probably one of the most legendary canyons to hike in all of Zion National Park."

Zion national-park.com - "The Zion Narrows deserves its reputation as one of the best, if not the best, hike in the National Park System."

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