Most riders take two to three and a half hours to ride up Mount Lemmon from the bottom of the Catalina Highway to Summerhaven, the village near the top. Going on to the very top adds another 20 to 40 minutes. Add about 45 minutes for the descent and the time you spend stopped, and the ride from the bottom to Summerhaven and back takes most people four and a half to five and a half hours, or closer to six if you go to the top.
Where you fall in that range comes down to how much power you can hold for two or three hours.
I've planned a full riding day around this climb, and these are the numbers I used to do it.
How long is the Mount Lemmon climb?
The Catalina Highway starts on the northeast edge of Tucson at about 2,800 feet and climbs to the observatory at the summit at 9,134 feet. That's nearly 28 miles and about 6,300 feet of climbing, at an average of 4.3 percent.
Most riders don't go all the way. They stop in Summerhaven, about 24.5 miles up, where the Cookie Cabin is. That's the climb most people mean when they say they rode Lemmon.
The grade is steady for most of the way, mostly 4 to 6 percent, with a mile marker every mile so you always know how much is left. Two things break the pattern. A little past mile 21 the road drops for about two miles, so you lose a few hundred feet you'll have to climb again. And the last 2.6 miles, past Summerhaven to the top, average about 8 percent. They're the steepest part of the mountain, and they're why the last stretch takes longer than its distance suggests.
How long does it take, by the power you can hold?
These times are worked out from the physics of the climb for a 176 pound rider on a 20 pound bike, riding steadily from the bottom to Summerhaven with no stops:
| Power you hold | Watts per kilogram | Time to Summerhaven |
|---|---|---|
| 160 watts | 2.0 | about 3 hours 10 minutes |
| 200 watts | 2.5 | about 2 hours 35 minutes |
| 240 watts | 3.0 | about 2 hours 15 minutes |
| 280 watts | 3.5 | about 2 hours |
| 320 watts | 4.0 | about 1 hour 50 minutes |
If you're lighter or heavier than that, go by the watts per kilogram column instead, using your body weight in kilograms.
Read the row for the power you can hold for the whole climb, which is lower than your FTP. For a two to three hour effort, most riders hold about three quarters of their FTP. So a rider with an FTP of 260 watts should read the 200 watt row, not the 240 one.
At the far end of the scale, the triathlete Lionel Sanders rode from mile zero to Ski Valley in 1 hour 34 minutes 21 seconds in March 2015, holding 348 watts. That set the Strava record for the climb at the time. That's a professional's number, and it isn't the one to plan around.
What adds time on the day?
The times above are the time you'd spend pedaling. A real day up Lemmon runs longer, for four reasons.
You'll stop. Windy Point at mile 14.7 is the best view on the mountain and almost everyone pulls over there. Don't count on water on the way up. The Forest Service says drinking water is inside the Palisades Visitor Center at milepost 19.9 when it's open, and at Mt. Bigelow and Spencer Canyon in summer only, so carry what you'll need. Two short stops add 15 to 30 minutes.
You'll start in the desert. The bottom of the climb is saguaro country, and in the afternoon it gets hot fast. Heat pushes your heart rate up at the same power, so a late start costs you time.
The air gets thinner. Summerhaven is close to 8,000 feet, and the higher you go the less power most riders can make. If you live near sea level, expect to feel it in the last hour.
And wind. On a windy day, the exposed stretches of a climb this long get noticeably slower.
How long does the descent take?
About 45 minutes from Summerhaven to the bottom for most riders, and a little more if you started at the top. It's 25 miles of long, fast turns, and it's not a rest.
The top runs 15 to 20 degrees cooler than the valley floor. You'll be sweaty from three hours of climbing, then you'll be moving at 30 miles an hour in cooler air. Bring a jacket and gloves for it, and stop when your hands get cold. Cold, tired hands on the brakes are the thing to watch on the way down.
How long is the whole ride, up and back?
For most riders, from the bottom of the Catalina Highway to Summerhaven and back is four and a half to five and a half hours, including a couple of stops. Lunch at the Cookie Cabin adds whatever time you give it.
If you're starting from a hotel in town, add the ride to the bottom. The miles to and from the climb turn a four hour ride into a full day.
Is Mount Lemmon hard?
It's long, not steep. Except for the final stretch to the top, the grade never gets steep enough to force you out of the saddle. What makes it hard is spending two or three hours climbing without a break, with no water you can count on along the way.
If you can ride a steady two hour climb at home, or a few back-to-back climbs adding up to the same thing, you can ride Lemmon. Gear the bike so you can sit and spin at 4 to 6 percent for that long. A compact crankset with a 30 or 32 tooth largest cog suits most riders. We wrote a separate piece on how to train for hilly bike rides if you want to get ready for it properly.
How to work out your own time
You don't need a power meter for this. Find the longest climb you ride regularly and look at how many vertical feet you climbed per hour on a steady effort. Strava shows elevation gained and time, so divide one by the other.
Mount Lemmon is roughly 5,000 to 5,500 feet of climbing from the bottom to Summerhaven, counting the downhill stretch you climb back out of. Divide that by your feet per hour and you have a fair estimate.
Use a long effort, not your best ten minutes. If you climb 2,500 feet an hour on a short hill, plan on closer to 2,000 on a three hour climb, and that difference is about half an hour on Lemmon. If you're not sure, plan for the slower number.
When should you ride it?
Tucson's riding season runs from late fall through spring, and February to April is the best of it. In summer, the bottom is too hot to start anywhere near midday, so a summer climb has to start at first light.
Whatever the season, start in the morning. You'll be climbing in the cool part of the day and back down before the afternoon heat.
How we ride a climb like Lemmon
When one of our trips includes a climb this long, here's how the day works.
On the flatter roads we ride together as one group. On a big climb there's no group pace. Everyone climbs at their own speed, the support vehicle moves from the front of the group to the back checking on everyone, and we regroup at the lookouts. So if you're a 3 hour rider and your friend is a 2 hour 15 rider, neither of you has to ride at the other's pace.
The support vehicle carries the layers for the descent, so you're not stuffing a jacket in your pocket for three hours on the way up. Lunch is at the top, then it's a careful descent. I ride every mile with the group. You can see which trips are running and what each day looks like on our trips page.
If you want to know more about the other rides in town, we wrote a guide to the best bike rides in Tucson. But if you only ride one, make it this one.