Mauna Loa, Island of Hawaii, USA -- by far the longest bike climb in the world.
We are fortunate to have documented the Top 10 longest bike climbs in the United States, located in seven different states (with three of the top four longest US bike climbs being in Hawaii). Below are a list and brief summary of each of the longest road bike climbs in the US.
LONGEST BIKE CLIMB IN THE US (AND WORLD)
MAUNA LOA, HAWAII
We have ridden this magnificent climb twice from Hilo (the southern and steeper route), and twice from Waikoloa (the northern and longer route). Mauna Loa is one of the great bike climbs in the United States and the world. How often can you say you have ridden the “#1” of anything in the world?
Mauna Loa, the longest bike climb in the world.
US Top 10 Most Epic Bike Climb
From the Waikoloa side, this monster climb is just over 62 miles and is therefore the longest and one of the most epic bike climbs in the world -- it will just flat out wear you down, but it is well worth the effort you’ll put into it. And, after riding the longest climb in the world, spend another day climbing Mauna Kea which is not only the world’s hardest climb by bike, but the sixth longest as well. These two volcanoes are just across “the saddle” from each other and each are clearly visible while riding up the other.
Photo on taken from upper Mauna Loa Observatory Road.
Mauna Kea in the background.
#2 LONGEST BIKE CLIMB IN THE US
TRAIL RIDGE, COLORADO
Cycling Trail Ridge, CO, a US Top 10 Most Scenic Bike Climb
43.9 miles (70.6 km) to 12,151’ (3,704m) gaining 7,770’ (2,367 m) at 3% average grade.
At 43.9 miles, Trail Ridge is the second longest bike climb in the United States and fifth longest in the world. Trail Ridge is also the highest continuous (i.e., not a dead end) paved road in the United States. Traversing Rocky Mountain National Park, this climb offers spectacular views along the giant switchbacks 20 miles below a summit that tops out at a whopping 12,000'.
#3 LONGEST BIKE CLIMB IN THE US
MAUNA KEA, BIG ISLAND, HAWAII
Located on Hawaii’s Big Island, Mauna Kea is the third longest climb in the US, the sixth in the world, and also the uncontested hardest bike climb in the world. Mauna Kea has it all: length (42.5 miles), altitude (sea level to nearly 14,000’), and gradient (the last 10 miles are from 8,120’ to 13,779’ at 10.7% average grade).
We have climbed Mauna Kea four times, in 2011, 2013, 2014, and 2018.
#4 LONGEST BIKE CLIMB IN US
HIGHWAY 33 TO PINE MOUNTAIN SUMMIT, CALIFORNIA
Ride 36 miles gaining 6,968’.
This climb might not be the most scenic of Southern California bike climbs, but we still consider it a bucket list climb simply because it is the longest bike climb in California and the sixth longest in the US. We begin at the northeastern edge of the beautiful town of Ojai (pop. 7,461 in 2010) in Ventura County and ride north up Highway 33. We enter the Los Padres National Forest (1,900,800 acres, established in 1936) in the first mile of the climb, and ride in the San Emigdio Mountains of the Pacific Coast Range as we climb towards Pine Mountain Summit on Highway 33.
#5 LONGEST BIKE CLIMB IN US
HALEAKALA, MAUI, HAWAII
Aerial sphere photo of the Haleakala Crater.
Ride 35.6 miles/57 km, gaining 9,988’/3,069m to 10,068’/3,044m at 5.3%.
We have ridden Haleakala four times from Paia, and once up Highway 37 from near the airport in Kahului. We recommend the Paia route as it is more scenic with less traffic. This climb is so difficult because it just wears you out, with 36 miles of straight climbing and generally between 5-7% average grade (the steepest mile averages only 7.8%). There are some of the greatest hairpins in the US on this climb, most of which are unobstructed (we are on a volcano after all), and the eight starting at mile 25 rival the Horseshoe Meadows Hairpins in length -- the five longest average 1.25 miles each! The wind is almost always blowing along the big hairpins, causing you to ride into is suffering for one leg, then you’ll turn and be loving life for the next mile and a quarter with the wind at your back.
Start the climb at sea level and finish 10,000’ later!
#6 LONGEST BIKE CLIMB IN UNITED STATES
HIGHWAY 31 EAST, UTAH
Ride 34 miles gaining 3,970’.
Located in the great state of Utah, the Highway 31 East climb gains nearly 4,000 feet of elevation over just about 34 miles, with an average grade of only 2.1%.
#7 LONGEST BIKE CLIMB IN UNITED STATES
ONYX SUMMIT, CALIFORNIA
Cycling Onyx Summit -- the longest bike climb in California, #5 US, #11 World.
Ride an amazing 30.5 miles gaining 7,328’ to peak elevation of 8,450 at 3.6%.
Onyx Summit is the longest and highest Southern California climb and quite a challenge. We have climbed Onyx during the spring of 2011 and 2012 for the super century “Breathless Agony” organized ride, and once in late November 2015. The climb can be quite hot during the late spring and summer, and quite cold and stormy during the late fall and winter months. The first two climbs were uneventful and very manageable with excellent support provided by the Breathless Agony organizers. The climb in late November (as can be seen from the slideshow below) was quite the adventure.
#8 LONGEST BIKE CLIMB IN UNITED STATES
HIGHWAY 143 EAST, UTAH
Ride 30.2 miles gaining 4,473’.
Another fun Utah climb! On Highway 143 East, you’ll ride just over 30 miles at an average grade of 2.4%, and you’ll gain almost 4,500 feet of elevation.
#9 LONGEST BIKE CLIMB IN THE US
BEAR LAKE SUMMIT, UTAH
Ride 30.1 miles gaining 3,280’.
This third Utah climb is another enjoyable one, riding through the Cache National Forest. You’ll ride just a touch over 30 miles, gaining almost 3,300 feet of elevation over an average 2% grade.
#10 LONGEST BIKE CLIMB IN THE US
BEARTOOTH PASS, MONTANA
30 miles, gaining 5,745’ to elevation 10,905’ at 3.3% average grade.
We defer to the late CBS news correspondent Charles Kuralt (“On the Road with Charles Kuralt”) for this category. Kuralt referred to Montana’s Beartooth Highway (and pass) near Yellowstone National Park as "the most beautiful drive in America.” Travelling the country for 25 years in a motorhome (going through six times in all) reporting on roads, beautiful scenery and landscape, and winning a Peabody Award for his efforts, Charles Kuralt seems to be a trusted and reliable source for this US bike climb category.
#12 LONGEST BIKE CLIMB IN THE US
MT. LEMMON, ARIZONA
Cycling Mt. Lemmon
Ride 28.8 miles gaining 7,160’ at 4.2% average grade.
In our experience, Mt. Lemmon in Tuscon, Arizona is the most popular bike climb in the US. Cyclists enjoy this ride so much because of the fantastic winter climate (not summer, although it is always cooler 7,000’ up the mountain than at the bottom of the climb), saguaro cactus at the start, and amazing hoodoos at the midway point.
ANOTHER BONUS RIDE:
#15 LONGEST BIKE CLIMB IN THE US
MT. EVANS, COLORADO
You cannot cycle any higher than this in North America.
Ride 27.4 miles gaining 6,744’ at 4.5% average grade.
Summit Lake mile 22.5.
To the summit: 5.4 miles gain 1,460’ at 4.6% to elevation 14,150’.