While May in Denver is warm, sunny, and snow-free, you’ll find very different conditions in much of the high country. This leads to problems when unprepared city-dwellers head to the hills in flip-flops and tank-tops. Mt Bierstadt in particular gets a lot of visits from enthusiastic yet unprepared hikers heading up its slopes in May. Here’s a few tips and route information to help you while hiking Mt Bierstadt in May.
Checking the Weather & Snow Conditions
One of the biggest obstacles to spring climbing is the unpredictable weather and snow. Depending on the week, you may find warm weather with little snow, or freezing temperatures and blizzard-like conditions. Planning your hike around “weather windows” where good conditions are expected is key for a successful and safe hike. While there are a few different places to get weather information, I usually use https://www.mountain-forecast.com/ and https://14ers.com/php14ers/weather.php but you can also utilize http://www.weather.com and use a town or city near the mountain. For the weather forecast, consider the following:
- What is the expected temperature, wind, precipitation and cloud cover on the day of your hike? Plan to be ready for them (with a margin for error).
- Are there any major storm systems or temperature drops before or after your hike? If so use caution, as these may arrive early, or come late.
For snow condition reports, there are great government sources for checking snow depth in the Front Range. This information is key for hiking Mt Bierstadt in May. For a map, visit the NOAA Snow Cover map here. Alternatively, you can compare current year snow totals to average and previous years here to get a better idea of what to expect, compared to the past. You should also check the peak conditions report on 14ers.com here. If the sources indicate there will be a lot of snow, consider checking the avalanche conditions here. You should also be prepared with snowshoes and traction gear. In light years with less snow, it is likely possible to ascend with just micro-spikes.
Packing Gear & Planning Your Trip
If you find a weather window, and snow conditions are reasonable, you can begin planning your trip in earnest. This really means three things. First, you need to pack appropriately. This means bringing the winter ten essentials (there will be snow!), along with layers to keep warm. You can read more about packing in my Guide to Packing for 14ers. Second, you should review the route using maps and trip reports. I recommend using 14ers.com, along with my information below.Third, leave detailed written plans, and your expected return time, with a trusted friend or relative back home. The Guanella Pass Trailhead is easily accessible, but following storms you may prefer a car with 4WD and good traction.
Hiking Mt Bierstadt in May: The Route
For numerous reasons, Guanella Pass closes each year from approximately October through late May. Usually you can park at the bottom of the final set of switchbacks on the road leading to the trailhead, about 1 mile below. When hiking Mt Bierstadt in May, this small parking lot can fill fast, so it’s a good idea to get an early start. The snow also begins to melt rapidly during May once the sun rises, which leads to difficult postholing through deep, wet snow. I recommend getting a pre-dawn start in May so you can beat the melt and conditions that come with it. One you park, here’s the route you should take hiking Mt Bierstadt in May.
Part 1: The Approach Road
Starting up the approach road, you also have a few options. Start out heading up the road, until you reach the first hard right turn. You should take the cutoff route here to avoid the next section of road, which passes beneath significant Avy terrain (there are usually tracks going up the road, but ignore them!). The route meanders through the woods, with a few steep sections, before connecting up with the road above.

Continue up the road until you reach another hard right turn. Here you have a choice. The formal route continues following the road up the switchbacks until it meets the parking lot and trailhead. However, you will drop down several hundred feet after leaving the trailhead. To avoid this unnecessary elevation gain, many people head directly into the willows at this Hard Right to meet up with the main trail (see the map below). It avoids elevation but you will need to navigate deep snow, buried willows, and a confusing route. If you’re new, I advise you to follow the road (I once got lost here for 2 hours – not fun!).
Part 2: The Willows
The Willows section, directly following where the two trail sections meet back up, is actually the hardest part of climbing Mt Bierstadt in the winter. During summer there’s an easy to follow path through the bottom of the creek. However in snowy conditions, all traces of the trail are buried beneath snow. If you are able to follow the trail left by others, try to do so. If you’re lucky and there’s been a lot of snowmelt, the trail may be easy to follow – it really depends on the conditions.
Take your time during this section, and if you think you are off-route, backtrack and try to get back. Trying to forge your own path in the deep snow will lead to post-holing, depleting your energy for the climb ahead. Few who do so end up summiting successfully. Be wary of tracks leading off from the trench – they are often dead ends.
Part 3: The West Slopes

As you climb higher up above the creek below, you’ll be aiming for a ramp that allows you to climb up onto the Western Slopes of Mt. Bierstadt (See the below picture). Usually this section is scoured by the wind, so you’ll be able to stash your snowshoes here. Find a spot not obvious from the trail, but easy to recognize on your way down. Continue up the Western Slopes – you’ve made it over halfway up the peak! Only one secion left for hiking Mt Bierstadt in May.
Part 4: The Crux Scramble
After what may feel like hours, you’ll reach the summit ridge. On my first attempt at climbing Mt Bierstadt in winter, I turned around here amid deteriorating conditions. It’s a good place to stop and decide whether to continue to the top. There is usually a well developed cornice here, rising above Abyss Lake below you. Enjoy the view, but make sure you stay at least 6-8 feet back away from the edge, as a cornice is unsupported and can break far from the edge.
Turn to your left to face the final scramble to the summit. This section is the least predictable in terms of snow conditions, as it depends on wind and snowfall conditions. It may be bare rock, in which case you can take off your traction, but it could also be a mess of snow, ice and rock intermixed. In that context, microspike or even crampons make sense. An ice axe is usually unnecessary given the large amount of rocks. Look for cairns to help guide your route, aiming upward toward the summit. After 30 minutes or so, you should suddenly come across the summit – what a glorious sight to behold!
View From the Summit
Before you head down from the peak, take a few minutes to enjoy the view. Looking East, you can see the Denver region below. Looking West, you can see the twin 14ers Grays & Torreys Peak, along with the Tenmile & Mosquito Range below. Take your time on your descent, and enjoy a warm drink of cocoa or coffee back at the trailhead!
Good luck hiking Mt Bierstadt in May!