Most trips to Winter Park start with the same drive: I-70 out of Denver, then up and over Berthoud Pass. In summer it's a pretty hour and a half. In winter it's the part of the day you plan around. Here's the route, what the law asks of your car, what happens when the pass closes, and how to time it.
Road rules and advice below are from the Colorado Department of Transportation and Colorado State Patrol, as reported for the 2025–26 season. Check COtrip for live conditions on the day.
- Distance from Denver
- About 67 miles
- Route
- I-70 west to Empire (exit 232), then US-40 north
- High point
- Berthoud Pass, 11,307 feet
- Good-weather drive
- About 1.5 hours from downtown Denver
- Traction Law season
- September 1 to May 31
- Live conditions
- COtrip.org and the COtrip Planner app
The route over Berthoud Pass
From Denver, take I-70 west into the mountains and leave at exit 232 for Empire. US-40 then climbs north for about 13 miles to the top of Berthoud Pass, crosses the Continental Divide at 11,307 feet, and drops down the other side to the resort and the town of Winter Park (Winter Park Lodging Co. puts the whole trip at 67 miles).
Two things make this drive different from the rest of the I-70 ski commute:
- You leave I-70 before the Eisenhower Tunnel. Empire is east of the tunnel, so you skip the climb to Loveland Pass and the tunnel queues that slow the drive to Summit County.
- The pass is the hard part. Both sides of Berthoud have steep grades and tight switchbacks on a two-lane road. In a storm, most of the extra time on this drive is spent here, not on the interstate.
Fill up in Denver or Idaho Springs. There's little on US-40 between Empire and Winter Park.
The Traction Law: what your car needs
From September 1 to May 31, CDOT can switch on Colorado's Passenger Vehicle Traction Law on mountain roads, including I-70 and US-40, whenever conditions call for it (Summit Daily). When it's on, every passenger car needs one of these:
- Winter-rated tires with enough tread. All-weather, mud and snow (M+S or M/S) or mountain-snowflake tires, with at least 3/16 inch of tread. That applies to four-wheel and all-wheel drive cars too.
- Chains or an approved traction device on at least two drive tires, if the tires don't qualify.
A quick tread check: push a quarter into the tread upside down. If you can see all of George Washington's head, you're under 3/16 inch.
When conditions get worse, CDOT can escalate to the Chain Law. That is mostly aimed at commercial trucks, which must carry chains on US-40 west of Empire all winter (Post Independent). Passenger cars rarely see it, but when it's on, everyone needs chains or a traction device.
Check a rental before you leave the lot. A rental car is held to the same rule. Look for the M+S or snowflake marking on the sidewall and check the tread before you drive away, and ask for all-wheel drive if a storm is forecast.
When Berthoud Pass closes
CDOT closes US-40 over Berthoud Pass during and after heavy snow for avalanche control, and for crashes and spin-outs. Planned avalanche work usually happens early in the morning, and the road typically reopens within a few hours. In March 2026 an avalanche closed the road between Robbers Roost and the Mary Jane side of the resort (Hoodline).
If the pass is closed and you can't wait, the detour is long. It runs through the Eisenhower Tunnel to Silverthorne, north on Highway 9 to Kremmling, then east on US-40 through Granby to Winter Park. That's roughly 150 miles and close to three hours in good conditions (Blue Sky Limo). On most closure days, waiting it out in Idaho Springs or Empire is faster.
Before you leave, check COtrip for "US-40 Berthoud Pass" and sign up for its text alerts.
Timing a weekend: up early, home late
The drive up is rarely the problem. The drive home is.
- Going up: leave Denver before 7am on weekends and powder days. You'll beat most of the I-70 traffic and get a better choice of parking at the resort.
- Coming home: CDOT asks drivers to avoid the mountain corridor between 1pm and 7pm on weekends and holidays. On Sundays, eastbound I-70 can be slow from 11am to 8pm (CDOT). You join that traffic at Empire after coming down the pass.
- The easy fix: ski until close, eat dinner in town, and drive home after 7pm. Or stay Sunday night and drive down early on Monday, which CDOT also suggests.
What to keep in the car
CDOT's winter list is short: a full tank, winter tires, and an emergency kit with extra clothing, food, water and batteries. For Berthoud specifically, add:
- An ice scraper and a snow brush. Cars parked all day at 9,000 feet come back buried.
- Washer fluid rated well below freezing. Road spray on US-40 empties a reservoir fast.
- A phone charger. Cell coverage is patchy near the top of the pass.
Skipping the drive
Two ways to take Berthoud Pass out of your ski day:
- The train. On winter weekends the Winter Park Express runs from Denver Union Station to the base of the resort, with no pass, no traction rules and no parking.
- Staying up. If you're driving up every weekend, a season based at the mountain changes the maths. A U9200 Alpine Club membership comes with a reserved parking space at a clubhouse on the Corridor trail between the Winter Park and Mary Jane bases, so a late arrival after a pass closure doesn't cost you a parking spot. Living slope-side is another step further: what a year in Winter Park costs runs the numbers.
For what the rest of the day costs once you arrive, see what a day skiing Winter Park actually costs.