The cross is the symbol of Christianity, so it is intriguing that Mountain of the Holy Cross — an immense natural formation of a perpetual cross — exists in Colorado, south of the Vail Mountain resort.

Mountain of the Holy Cross isn't just any mountain. It is one of Colorado's "14ers" (14,000-foot-peaks), of which there are 58.

The mountain used to be a national monument, and many Christians made rugged pilgrimages there in the early 20th century for its reputed healing powers.

How big is the cross?

Simply gigantic. The arm is about 750 feet across and its vertical length is at least twice that, at about 1,500 feet high.

Ice and snow accumulate in a deep gully to form the shape of the white cross on the mountain's northeast face. Located in the Sawatch Range, the Holy Cross is also only about 15 miles from Vail Resort and visible from the 10,300-foot summit at the Eagle's Nest of Vail.

Today Vail Mountain Resort has a wedding deck that faces directly toward the Mountain of the Holy Cross.

"There are tons of weddings performed there during the summer," Katie Coakley, a spokeswoman for Vail Resort, said. "By Labor Day, you'll start to have times that it's not able to be seen, but it'll melt the next day. It's usually October or November when it's not visible."

A sunrise Easter morning service at Vail's Eagle's Nest is a regular religious event held annually.

There's also the Mount of the Holy Cross Lutheran Church in the Vail, Colorado Valley, named after the unusual mountain. Pastor Scott K. Beebe said pilgrimages to the cross were revived in 1976 as a Bicentennial event after a 37-year lapse. Since then, Holy Cross Lutheran has continued them. This year's trek is July 31-Aug. 1.

"Mount of the Holy Cross is indeed a majestic peak, which my wife and I had the privilege of climbing several years ago," the Rev. Beebe said. "It is a fascinating mountain with an intriguing history."

This mountain was just a legend that few believed really existed in the late 19th century. This obscurity was compounded not only by the mountain's remote nature — some 100 miles southwest of Denver — but also that many map makers of the era misplaced the formation by as much as 30 miles.

Sam Bowles was the first recorded visitor to see the cross, from Grays Peak, about 40 miles away, in the late 1860s.

He wrote in his 1869 book, "The Switzerland of America," "Over one of the largest and finest, the snow fields lay in the form of an immense cross, and by this it is known in all the territory. It is as if God has set his sign, his seal, his promise there — a beacon upon the very center of the continent to all its people and all its generations..."