"It never happened before, and it's not likely to happen again.
Wednesday before dusk, rangers at Zion National Park, in southern Utah, blocked all traffic on the highway that crosses the park so that 300 people holding rare and precious tickets could walk through the historic, pitch-black and narrow Zion Tunnel.
The tickets were snapped up in four hours when they were offered in June. And those lucky few ticket holders traveled from across the West to hike the mile-long tunnel, which was carved out in the late 1920s, 800 feet above the floor of Zion Canyon and 20 feet inside a sandstone cliff.
The Zion Tunnel Walk was part of Zion's centennial celebration. It showed how a man-made feature in a national park can become as important as the natural and scenic features the park was established to protect."