Hiking mountains is one of the most beloved outdoor pastimes in the U.S. Yet few people realize just how dangerous some of these rather unsuspecting peaks can be. Even the most avid outdoorsmen have lost their lives due to sudden weather change, rocking footing, or other unforeseen causes. So next time you’re planning an outdoor adventure in the mountains, you may want to avoid the following peaks:

  1. Longs Peak, Colorado

Bryce Bradford/flickr

AJ Schroetlin/flickr Longs Peak, measuring 14,259 feet, is the only Colorado fourteener located in Rocky Mountain National Park. This relatively easy accessibility means that thousands of people attempt to climb this peak every year. And yet, it’s one of the most dangerous mountains in the U.S. Conquering the peak means beginning the hike at 3:00 a.m. to avoid any incoming thunderstorms, which can prove to be fatal if lightning strikes the peak.

  1. Mt. Washington, New Hampshire

Nicholas Erwin/flickr

Robert Linsdell/flickr New Hampshire’s Mount Washington resides at an elevation of 6,288 feet above sea level. While this peak may seem somewhat mild compared to others in the U.S., it’s truly one of the most volatile. The structure of the landscape funnels wind and storms coming from the northwest. In fact, the highest wind speed ever recorded by man (231 MPH) took place here. Needless to say, it’s an incredibly dangerous place to be when a storm comes through, especially considering the weather can change in a matter of minutes.

  1. Mt. San Antonio, California

Brian Altmeyer/flickr

Don Davis/flickr Also known as Mount Baldy, Mount San Antonio is the highest peak in Los Angeles County, residing at 10,000 feet. What makes this peak dangerous is the unpredictable weather at high altitude. For example, temperatures at the peak will almost always be 35 degrees colder than what’s measured at sea level. For this reason, it’s not uncommon for hikers to require rescue via helicopter from this precarious mountain trail.

  1. Mt. Rainier, Washington

Anupam_ts/flickr

turcottes78/flickr It’s hard to imagine a U.S. mountain peak more iconic than Mt. Rainier in Washington. Rising 14,400 feet above sea level, this peak is covered in glaciers and snow year round. Hiking to the top requires ice picks, crampons, and extensive preparation. This peak attracts over 10,000 hikers annually, who must be wary of avalanches and other harsh conditions of the climb.

  1. Half Dome, California

Stew Dean/flickr

lex Proimos/flickr Just a photograph of the view from the top of Half Dome in Yosemite is enough to make your stomach drop. The final summit of the peak requires hikers to ascend 400 feet via wire cables. Many have fallen or slipped on this part of the climb, which is why the National Parks Service has implemented a permit requirement to hike this peak.

Have you ascended any of these incredibly dangerous mountain peaks in the U.S.? Be sure to share your experience with us! Looking for more mountains? Be sure to check out These 18 Majestic Mountain Views That Will Leave You In Awe.

Bryce Bradford/flickr

AJ Schroetlin/flickr

Longs Peak, measuring 14,259 feet, is the only Colorado fourteener located in Rocky Mountain National Park. This relatively easy accessibility means that thousands of people attempt to climb this peak every year. And yet, it’s one of the most dangerous mountains in the U.S. Conquering the peak means beginning the hike at 3:00 a.m. to avoid any incoming thunderstorms, which can prove to be fatal if lightning strikes the peak.

Nicholas Erwin/flickr

Robert Linsdell/flickr

New Hampshire’s Mount Washington resides at an elevation of 6,288 feet above sea level. While this peak may seem somewhat mild compared to others in the U.S., it’s truly one of the most volatile. The structure of the landscape funnels wind and storms coming from the northwest. In fact, the highest wind speed ever recorded by man (231 MPH) took place here. Needless to say, it’s an incredibly dangerous place to be when a storm comes through, especially considering the weather can change in a matter of minutes.

Brian Altmeyer/flickr

Don Davis/flickr

Also known as Mount Baldy, Mount San Antonio is the highest peak in Los Angeles County, residing at 10,000 feet. What makes this peak dangerous is the unpredictable weather at high altitude. For example, temperatures at the peak will almost always be 35 degrees colder than what’s measured at sea level. For this reason, it’s not uncommon for hikers to require rescue via helicopter from this precarious mountain trail.

Anupam_ts/flickr

turcottes78/flickr

It’s hard to imagine a U.S. mountain peak more iconic than Mt. Rainier in Washington. Rising 14,400 feet above sea level, this peak is covered in glaciers and snow year round. Hiking to the top requires ice picks, crampons, and extensive preparation. This peak attracts over 10,000 hikers annually, who must be wary of avalanches and other harsh conditions of the climb.

Stew Dean/flickr

lex Proimos/flickr

Just a photograph of the view from the top of Half Dome in Yosemite is enough to make your stomach drop. The final summit of the peak requires hikers to ascend 400 feet via wire cables. Many have fallen or slipped on this part of the climb, which is why the National Parks Service has implemented a permit requirement to hike this peak.

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