Leadville, Colorado, founded in 1877 at an elevation of 10,152 feet, has seen plenty of change. Once the second largest city in Colorado despite its inconvenient location, the mining community that helped build this area left the “Two-Mile High City” with a storied past.

When it came to mining, Leadville was one of the most successful communities in the United States, producing an estimated $5 billion worth of product through 1967.

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Leadville’s mining history does have some rough spots, including a strike in the late 1800s that resulted in five  known deaths. This incident happened in the wake of a time where booming populations and lots of money attracted several infamous gunslingers to the area, causing Leadville to be known as one of the most lawless and violent towns in the West.

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During its booming years in the late 1870s, many experts put the population of the tiny town of Leadville at around 18,000, while some say it was closer to 40,000. To put this in perspective, Leadville is currently home to around 2,500 residents. That’s a big  difference, especially when one considers the lack of amenities and infrastructure that would have plagued a remote mountain town nearly 150 years ago.

During the early 1940s, World War II created a huge demand for molybdenum, an element that can be used to harden steel. As a result, Leadville boomed once again, with 75 percent of the world’s molybdenum mined at Leadville’s Climax mine. This mine continued to grow, eventually reaching its peak in 1980, during which time it was the largest underground mine in the world.

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Today, Leadville, Colorado is a destination for outdoorsy folks and endurance enthusiasts, with several 14,000 foot mountains in the area, including Mount Elbert and Mount Massive. Its mountainous terrain attracts plenty of high-altitude races, including the famous Leadville 100, an ultramarathon. The record time for this 100-mile trail run was set by a man named Matt Carpenter at 15 hours, 42 minutes, and 59 seconds.

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