Last summer, my 7-year-old son and I set out to summit a 10,500-foot peak in the Colorado Rockies, a trail I'd hiked a dozen times as a teenager. I'd packed his favorite chocolate trail mix, his dinosaur-shaped water bottle, and a camera to capture the glacial alpine lake at the top. Halfway up, at 9,000 feet, he stopped walking, buried his face in my leg, and said his tummy hurt. I brushed it off as hunger at first---he'd been too excited to eat breakfast that morning, bouncing around the trailhead while I laced my boots. But 10 minutes later, he threw up, and his usually chatty, curious self went completely quiet, refusing to even look at the chipmunks darting around the trail. That's when I realized: I'd made the rookie mistake of treating a high-altitude hike exactly like the low-elevation day trips we did every weekend around our hometown. Altitude sickness doesn't care that you're 7 years old, that you've hiked 20 miles at sea level, or that you've been begging to see that lake for six months. High-altitude family hikes (generally defined as trails above 8,000 feet) offer some of the most magical, unforgettable experiences for kids: wildflower meadows that stretch for miles, icy streams they can splash in for hours, and views that make even the most bored 10-year-old stop scrolling and stare. But kids are far more vulnerable to altitude-related illnesses than adults, and their symptoms often don't look like the "classic" headache and nausea most parents are warned about. The good news? With a little extra planning and a whole lot of listening to your kids, you can keep your young explorers safe without sacrificing the adventure.
Start With Smart Pre-Trip Planning
The single biggest mistake families make with high-altitude hikes is rushing the acclimatization process. It's tempting to drive straight from your sea-level home to a 10,000-foot trailhead and start hiking the same day, but that's a fast track to altitude sickness for everyone in your group, especially kids. There's no universal acclimatization timeline for kids---some 8-year-olds adjust to 10,000 feet in 24 hours, others need 3 full days. Go at your slowest kid's pace, not your fastest. A good rule of thumb: for every 1,000 feet of elevation gain above 8,000 feet, build in an extra 24 hours of low-stakes acclimation before tackling big hikes. If you're planning a trip that maxes out at 11,000 feet, plan to spend 2-3 days at a mid-elevation basecamp (6,000-7,000 feet) first, taking short, easy walks around the campground or nearby easy trails to let your kids' bodies adjust to the thinner air. Avoid letting kids sleep at high elevation on the first night of your trip if you can---sleeping at altitude increases the risk of altitude sickness dramatically. Before you book anything, check in with your pediatrician, especially if your child has asthma, recurring respiratory infections, or has had altitude sickness in the past. They can give you age-appropriate guidance on over-the-counter medications to pack, and help you decide if your child is ready for high-altitude adventures. Also, pick your trail carefully for your first high-altitude hike with kids. Skip trails that hit 12,000+ feet on day one, and opt for routes with minimal elevation gain per mile, plenty of turnaround points, and easy access to ranger stations. The goal for your first trip isn't to summit a 14er (or any big peak, for that matter)---it's to build positive memories so your kids want to come back for more.
Know the Red Flags: Altitude Symptoms in Kids Don't Always Look "Normal"
Most parents know the classic signs of altitude sickness: headache, nausea, dizziness, and fatigue. But kids, especially young kids who can't fully articulate how they feel, often show symptoms that look like regular kid behavior, which makes them easy to miss if you're not looking out for them:
- Mild acute mountain sickness (AMS) might look like a cranky, clingy kid who refuses to eat their trail snack, complains of a vague stomach ache, or is uncharacteristically tired after just 30 minutes of hiking. They might also have a mild headache, but they won't always be able to name that specific feeling.
- Moderate to severe altitude sickness can look like extreme lethargy (they can't be woken up easily, or don't want to move at all), confusion, difficulty breathing even at rest, blue or gray lips/fingernails, loss of coordination, or persistent vomiting that won't stop. There's one non-negotiable rule for high-altitude hiking with kids: if you suspect altitude sickness, descend immediately. Even a drop of 1,000-2,000 feet in elevation can drastically improve symptoms in a matter of hours. Don't push through "just a little headache" or brush off complaints as "being dramatic" or "tired from the hike"---the only proven cure for altitude sickness is lower elevation, and waiting can turn mild AMS into life-threatening high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE), both of which require immediate emergency medical care.
On-Trail Habits That Keep Everyone Safe
Once you're on the trail, small, consistent habits make the biggest difference in preventing altitude-related issues and keeping the trip fun for everyone:
- Hydrate like it's your job (because it is). Altitude dehydrates you twice as fast as at sea level, and kids are even worse at noticing when they're thirsty. Make a silly family rule that everyone takes a sip of water every 15 minutes, even if they say they don't want it. Avoid sugary sports drinks, which can worsen dehydration---stick to plain water or electrolyte tablets mixed into water for longer hikes.
- Fuel early and often. High altitude suppresses appetite, so kids might not want to eat big, heavy meals. Pack small, easy, calorie-dense snacks (granola bars, dried mango, cheese sticks, pretzels) and encourage them to eat a little every hour, even if it's just a few bites. Keeping blood sugar up helps the body adjust to thinner air and prevents energy crashes halfway up the mountain.
- Layer up, even if the sun is shining. High-altitude weather can change from 75 degrees and sunny to snow and 30-degree wind in 10 minutes, and kids lose body heat way faster than adults---they also produce more heat when hiking, so they might not notice when they're getting cold until it's too late. Pack a waterproof shell, a warm fleece, a beanie, and extra socks for every kid, even if the forecast looks perfect. Avoid cotton layers, which stay wet and cold if it rains or if your kid sweats heavily on the climb.
- Take extra breaks, and listen when they say they're tired. Kids will often push through discomfort to please you, so don't wait for them to ask for a break. Plan for 5-minute rest stops every 30 minutes, and stop immediately if your child complains of a headache, stomach ache, or extreme fatigue. There's no prize for finishing a hike faster than everyone else, and turning around early is way better than having to call for a rescue halfway down the mountain.
Pack for the Worst-Case Scenario (Even If You Don't Think You'll Need It)
Even the best-planned trips can go wrong, especially in remote high-altitude areas where cell service is non-existent. Pack these non-negotiable items in your daypack, not just your kid's pack, so you have easy access to them if you need them:
- A satellite communicator (like a Garmin inReach or Zoleo) that lets you send emergency messages or call for help even if you have no cell service. Most high-altitude trailheads have no signal, and this $100 piece of gear could save your life if someone gets severely injured or lost.
- A pediatrician-approved altitude medication kit: children's acetaminophen for headaches and fever, anti-nausea medication (only if prescribed by your doctor), and your child's regular rescue medications if they have asthma or allergies.
- A printed copy of your trail map, with marked ranger stations, trailheads, and emergency access points. Share your full itinerary, including your expected return time, with a friend or family member who isn't on the hike, so they can call for help if you don't check in when you're supposed to.
- A small emergency blanket, a spare set of warm dry clothes, and extra high-calorie snacks (like energy gels or peanut butter packets) in case you get stranded and have to wait for rescue.
When my son got sick on that 10,500-foot trail, we turned around immediately, and spent the next two days at a 7,000-foot campground taking short, easy walks around the lake, letting him run around and play in the dirt to get used to the altitude without pushing him to hike. Two days later, we tried the same trail again, and he summited without a single complaint, spending 45 minutes throwing pebbles into the alpine lake at the top and demanding we come back next summer to camp there. That extra two days of acclimation didn't ruin our trip---it made it.
The Bottom Line: Adventure Over Summits
There's a weird, unspoken pressure in the hiking community to bag as many summits as possible, to check peaks off a list, to prove you're "hardcore" enough to handle high altitude and tough trails. But when you're hiking with kids, the only goal that matters is keeping them safe and helping them love the outdoors enough to want to come back for the rest of their lives. If your kid complains of a headache at 8,500 feet? Turn around. If they want to stop and look at butterflies for 20 minutes instead of hiking to the summit? Stop. If you have to skip a high-altitude trip entirely this year because you don't have time to acclimate? That's okay. The mountain will always be there. The memories you make with your kids, even if they don't involve a summit selfie or a checkmark on a peak list, will last a lot longer.