According to lore, in 1907, one Alaska bar patron in the small town of Seward bet another that he couldn’t run up and down the town’s prominent downtown peak in under an hour. The bet was taken, and from that moment the race was on. Today, the United States’ oldest trail race is held every 4 July in Seward on Alaska’s Kenai Peninsula.

Now in its 85th year , the Mount Marathon race is much more than a casual trail run. The three-mile race is steep, with 3,022ft of elevation gain and loss, and there’s no official course. Participants begin on 4th Avenue in Seward’s historic downtown and run about a half mile through cheering crowds to the base of the mountain, where they begin the steep ascent. They must scale the near-vertical base by climbing rocks and tree roots like ladders -- or take a longer switchback trail -- and then begin an arduous hike uphill, sliding on mud and grasping at alders and shrubs to pull themselves up.

Once at the summit soft shale allows runners to dig their heels in and descend rapidly; the fastest can get from summit to base in less than 15 minutes (and the original bet has long been beaten – male winners today generally finish the entire race in less than 45 minutes and the women under 55). After reaching the halfway mark on the way down, competitors enter “the chute” (an avalanche chute when filled with snow in winter), which quickly turns into a v-shaped canyon complete with a rushing stream. Racers follow the stream -- jumping off small cliffs and through waterfalls -- and a final rock face at the base creates one of the last challenges, requiring concentration and crab-walking to climb down. Finally, they hit the street on wobbly legs and run back to 4th Avenue amid a roaring crowd. The competitors are always muddy, and quite often bloody.

Even if you’re up to the challenge of racing Mount Marathon, the difficulty begins at registration; the competition uses a lottery and seniority system to select runners, and in 2012 only 4% of men and 9% of women who applied got in. Though it started as a small hometown race, runners come from around the world to compete.  A few slots are set aside for an auction the night before the race, and many sell for more than $1,000 (lottery tickets are only $65). Once in the race, runners must compete for 10 years in a row or else they lose their spot.

Watching the race, however, is a Fourth of July tradition. Though Seward is home to more than 3,000 residents, the town bloats to more than 40,000 visitors around this date. Every available spot of land is taken by a tent, and the usually quiet single road in and out of town can be backed up for hours before, during and after the holiday.