A stunning canyon in Utah's Zion National Park is being dubbed a 'nature-made subway'.
The 'cylindrical slot' canyon is located in between two peaks called the North and South Guardian Angels.
And it is so popular only 80 hiker permits are issued per day, and a lottery reservation system is in place from March to November to handle the high demand of peak season, according to Grind TV.
But getting to the canyon is no easy task. Firstly, while the subway itself is only a quarter of a mile long, it's a 9.5-mile round-trip to find it.
What's more, the trip has been deemed 'strenuous', with route-finding, swimming and rappelling involved on the way.
Hikers are advised to go with somebody that knows the area, but groups are restricted to no more than 12.
It might be a real challenge to find it, but it looks like the effort is worth it in the end.
See more wonderful pics at williehuangphotography.com
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