Cars and driving - Mountains

Mosquito Pass is a seasonal 4WD road, not a year-round route to Leadville

Mosquito Pass connects Alma and Leadville over a very high, rocky road that is usually open only for a short stretch of summer and needs a high-clearance 4WD vehicle.

Published June 10, 2026 - Last verified June 11, 2026

Look at a map and Mosquito Pass appears to offer a shortcut from Alma, in Park County, over the Mosquito Range to Leadville. In practice it is a rough mountain road, not a normal route between the two towns. The Forest Service describes it as steep, very rocky, and best for a high-clearance four-wheel-drive vehicle.

The road climbs to one of the highest drivable points in Colorado, and snow lingers up there long into the year. It is usually open only for a short window in summer, after the snow finally melts, and then it closes again. Those dates shift from year to year with the weather, so a date that worked one summer may be buried in snow the next.

This matters for newcomers in a couple of ways. A navigation app may route you over a pass like this without knowing it is a 4WD-only road or that it is closed. And a low-clearance car or a sudden storm at that elevation can turn a scenic drive into a stuck-vehicle problem far from help.

If you want to drive Mosquito Pass, treat it as a planned backcountry trip, not a commute. Check the current road status and conditions with the Pike-San Isabel National Forests before you start.

Filed under: Cars and driving Park County

Keep reading

Related Porch Notes

More notes from Park County and nearby topics.

Cars and driving

Getting in and out of Park County means driving mountain passes

Major routes into Park County climb over high passes like Kenosha and Hoosier, where winter weather, traction and chain laws, and temporary closures are part of normal travel.

Read note ->

History and culture

Every July, Fairplay races burros over a 13,000-foot pass

Fairplay's Burro Days festival each July features the World Championship Pack Burro Race, where runners and their burros climb over Mosquito Pass on a course of more than 29 miles.

Read note ->

History and culture

Fairplay was born in the gold rush, and Alma grew with the mines that followed

Fairplay began as a gold-rush camp, Alma grew later as a supply and smelting town for nearby mines, and the mining era still shapes the towns, place names, and disturbed ground around South Park.

Read note ->

Outdoors and wildfire

The DeCaLiBron 14ers above Alma share one trailhead at Kite Lake

Four high peaks above Alma — Democrat, Cameron, Lincoln, and Bross — are reached from the Kite Lake trailhead, but the Mount Bross summit has been on private land with restricted access.

Read note ->

Outdoors and wildfire

Windy Ridge's Wind-Sculpted Bristlecones Above Alma

On a high shoulder of Mount Bross above Alma, a Forest Service scenic area protects gnarled bristlecone pines, some over a thousand years old.

Read note ->

Cars and driving

Mosquito Pass is a rough, high four-wheel-drive road open only briefly each year

The Mosquito Pass road east of Leadville is a steep, rocky high-clearance four-wheel-drive route that is usually open for about six to eight weeks after the summer snowmelt.

Read note ->

Sources and review

Where this information comes from

This note uses official or primary sources where practical. Local details can change, so confirm before acting.

Last reviewed: June 11, 2026