Six Tunnels to Hoover Dam Half Marathon, 12K, 5K & 1-Mile

Saturday, March 13, 2021 • Boulder City, NV • Course Map

Combine a run through a desert-like environment, the crystal-blue waters of Nevada’s Lake Mead nearby and the majestic Hoover Dam in the distance, and then you’ll begin to get a feel for what it’s like to run the Six Tunnels to Hoover Dam St. Patrick’s Day Half Marathon, 12K & 5K Run, open to runners and walkers.

The course for the race, which takes runners along a mountainous trail road through the hills of Lake Mead National Recreational Area to the world-famous dam, was newly paved and graded two years ago, which makes for an even smoother race for participants.

Named for the tunnels along the converted railroad track trail road to and from the Dam (yes, runners and walkers will actually travel through the tunnels), the course once served as an access route for train cars and trucks hauling supplies to Hoover Dam.

Thanks to its original construction, the route offers largely smooth, gradual inclines and declines, though there are some big climbs on the route. The views are also spectacular, including the mountains around the lake, the desert sagebrush and other vegetation, and the tunnels themselves, a unique architectural feature to find at a road race.

Organizers add that because there is no vehicle traffic on this road, participants may take as long as they like to finish the race — another unusual perk for road races. The National Park Service notes that along the trail, it’s common to find wildlife including desert bighorn sheep, ravens and owls, and antelope ground squirrels, among other creatures.

Several hundred runners and walkers have finished the combined individual half marathon and 5K in recent years, in addition to dozens of half marathon two-person relay teams, so it’s definitely a well-attended race — sign up early, because the race can and often does sell out.

Race Weather & Climate

Located roughly 30 miles east of downtown Las Vegas and just miles from the southern shoreline of Lake Mead, Boulder City typically sees March temperatures that average between 46°F and 65°F, while rainfall is scarce here year-round, averaging just under an inch for the month (making March its wettest month of the year).

On the day of the race (March 13), the average low is 46°F and the average high is 66°F.

Past Results

Course Map

See the race route map for the Six Tunnels to Hoover Dam Half Marathon here.

Starting Time

  • 7:30 AM – half marathon
  • 7:35 AM – 12K run/walk
  • 7:45 AM – 1-mile stroll, 5K


  • $70 – $105 for the individual half marathon
  • $95 – $130 for the relay half marathon
  • $40 – $75 for the 12K
  • $30 – $65 for the 5K
  • $10 – $45 for the 1-mile


To reserve your spot in the 2021 running of Boulder City’s Six Tunnels to Hoover Dam Half Marathon, Relay or 5K race, register online at the event website here.

Official Race Website


Ever run in the Six Tunnels to Hoover Dam Half Marathon? Share your impressions here, or post your review in the Comments below.

See more races in: March, Nevada

2 comments… add one
  • Terrell Johnson February 12, 2015, 12:17 pm

    And here’s what another commenter, Christopher Murphy, said about the 2012 race on our old site: “Just ran it and there are plenty of steep hills and inclines. Only the first 5 miles was paved, the rest is dirt and gravel. A fun and challenging race but it’s harder than the description above.”

  • Terrell Johnson February 12, 2015, 12:17 pm

    Here’s what past commenter Arnell Dean Copperfield had to say about the race on our old site: “This is very challenging! I loved the climb but had no idea I had to climb some more, ugh. I am glad I ran it though. Hills are my favorite but after this half I now know what hills are. haha. My favorite part was running through the tunnels though I’m scared of the dark so I was a little freaked out and the climb at the top of the hill before you loop the course is an INTENSE climb! PREPARE YOURSELF!”


Leave a Comment