Gary Salzman/KTVB

The City of Rocks park turns twenty today - but the geology has been forming for thousands of years.

It's majestic, mystical and marked by history.     

The City of Rocks in south central Idaho formed eons ago, but in one way, it's barely out of its teens. 

Tuesday marks the 20th anniversary of congress designating the area as a national reserve.

For the “city,” nature acts as architect – using molten rock as its building material.

"Granite was buried and then became rock, but then there was mountain building that's pushing that rock more to the surface." said City of Rocks Superintendent Wallace Keck. 

Nature also acts as artist - using rain and wind to sculpt and shape. 

"I think that these rocks are so different from the other rocks that we have ever seen.  It's sometimes kind of scary," said tourist Joyce Lin. 

See the beauty of City of Rocks

The City of Rocks is about a 3 and a half hour drive from Boise - south of Burley and just outside the town of Almo.

Park Superintendent Wallace Keck says every year about 85,000 people come here from all over the U.S. and from more than a dozen countries.

They come to photograph the alien landscape and scale its world renowned granite formations.

Rock climbers like Matt Kilgore-Brown. 

"We heard about it online and you hear about it a lot in the climbing community.  It's pretty famous as a center of rock climbing," Kilgore-Brown said.

Some of the rocks they climb date back 2.5 billion years.

But this place is also pretty famous for its key role in more recent history.             

In the 1840s and 50s the City of Rocks was a key place along the California Trail.  Many of the people would pull their wagons right up to the rocks like this for shelter and camp for the night.  Many of them also left their mark in axle grease

"It's a place for leaving the message either for family member that are further behind or maybe the next wagon train behind or maybe next year," Keck said. "We actually have pictures, later in the 1860s pictures of standing on a wagon wheel painting a signature on the rock.”

Many of the 240,000 emigrants who passed through here not only wrote their names on the rocks, they wrote about this strange place in their diaries... like Margaret Frink did in 1850. 

"It is called the City of Rocks, but I think the name ‘Pyramid City’ more suitable,” Frink wrote. “It is a sublime, strange and wonderful scene, one of nature's most interesting works.”

For all these reasons Congress designated City of Rocks as a National Reserve on November 18th, 1988- one of only four such areas in the country.

It's a unique partnership between the State of Idaho and the National Park Service to protect, preserve and promote this gem in the Gem State. 

"Congress recognized how nationally significant the California Trail, the landscape and just the wonderful scenery and geology is to the nation and not just a state park," Keck said.

The scenery,

"It's far away from home, but I think it's worth the trip," tourist Lin said.

The geology.

"I mean we drove 15 hours to get here and it's been worth it," climber Kilgore-Brown said.

And the history.

"A lot of people do come and look for family names," Keck said.

The City of Rocks is open all year, but it does tend to get a lot of snow through the winter.

Before making a trip there, you should call the park for road conditions.