Boulder to Carter Lake Loop

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Boulder, CO, US

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Route Overview

BetweenRides

Midwest Routemeister

75 mi.

3,198 ft.

Starting from beautiful downtown Boulder, ride along the Colorado Rockies front range, through the Boulder flats up to the breathtaking Carter Lake Reservoir. Incredibly scenic route with the Rockies in the background for the whole ride. Come see why so many pro riders choose this area as their home base.

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Route Details

Your ride starts and ends at @poi[University Bicycles](2476002), an excellent bike shop located on historic Pearl St in downtown Boulder, one of my favorite places to visit in Colorado, particularly since my son lives there. Parking in downtown Boulder can be tough, but there is a @poi[city parking deck](2476001) located at Spruce St between Broadway and 11th St, a block North of Pearl St and just 3 blocks from the shop.

Boulder is a thriving mid-sized city located on the edge of the Rockies front range. Boulder is home to the pro team Cannondale Drapac (formerly Garmin-Sharp), run by former pro Jonathon Vaughters and includes some pretty famous riders, including Boulder native Taylor Phinney, son of Boulder's own Davis Phinney (Team 7-11) and Connie Carpenter (1984 Olympic Gold Medalist in Cycling).

Boulder is also home to the University of Colorado, the state's largest universtiy. Like most of the front range in Colorado, Boulder has a mild and dry climate. It's also a fine spot for biking, with choices through the trails around town, the Plains North, East and West, and finally as a gateway into the Rockies. With an average of 270+ days of sunshine a year and fairly mild temperatures, it's a cyclist's heaven virtually year round.

You'll start your ride heading @slice[West on Pearl St](d,0,568.72) before heading @slice[North Up 4th St](d,740.09,3464.71) for several warmup miles through some of Boulder's prettiest neighborhoods. You'll get your first views of the front range and wind your way over to busy @slice[Broadway St](d,5119.38,6993.26). It's a heavily traveled road, but Boulder abounds with cyclists and drivers will treat you with respect, as this is a favorite cycling route out of town. At the North end of town after the 4 mile mark, you'll head @slice[North on US Hwy 36](d,7126.99,16085.34). Again, have no fear, this is a heavily cycled road and it has a paved shoulder on each side, easily wide enough for two cyclists riding abreast. Depending on the day of the week, you will probably see dozens of other riders.

At mile 10, you'll head East on Nelson Rd, starting with a @slice[4 mile descent](d,16085.34,22385.43) into the flats Northeast of Boulder. If you're a flatlander like me, you'll enjoy the mostly level scenic roads. Next it's North on @slice[65th St](d,23220.77,25646.49), with rolling hills through farmland, ranches and horse stables. At around 16 miles, you'll go East on @slice[St Vrain Rd](d,25646.49,27749.58) and then North on @slice[75th St](d,27749.58,29154.3), crossing St Vrain Creek before heading into the tiny town of Hygiene, CO. If you're hungry, stop at the @poi[Crane Hollow Cafe](2476004) on your right, or @poi[Mary's Market & Deli](2476003) on your left. Best to stop at Mary's to fill your water bottles, as this is the last place to do so until you come to the Marina at Carters Lake at mile 34.

Continuing North from Hygiene, you'll be on @slice[rolling and flat roads](d,29154.3,45147.13), with the front range on your left and the great plains to your right. At mile 28, you'll head East on the @slice[5 mile long ascent up to Carter Lake](d,45249.13,51468.1). The final mile features some switchbacks and is quite steep. It's worth the ride, with a breathtaking view back East over the plains. The ride around the @slice[Eastern shores of Carter Lake Reservoir](d,51468.1,55309.24) crosses 3 different dams. Just East of the last dam is the @poi[Carter Lake Marina](2476005). Good place for a break and to refill your water bottles, as there won't be another chance until you pass through Hygiene again on your return trip.

After the Marina, you'll continue North on County Rd 31 and enjoy a @slice[3-1/2 mile descent](d,56414.02,61973.25) down from Carter Lake. You'll head East on @slice[Poll Hill Rd](d,58690.57,61991.93), enjoy long rolling hills and flats on @slice[County 29](d,62007.55,67214.9), @slice[County 12](d,67237.37,70004.64) and @slice[County 23](d,69977.49,73266.45), which take you back into the plains. From there you'll be on the same roads as the trip up to Carter Lake, until you head East on @slice[Wagonwheel Rd](d,77291.52,79641.06), then South on @slice[County 21](d,79682.26,82886.63), @slice[Yellowstone Rd](d,82877.29,83083.76) and @slice[95th St](d,83109.42,88794.31), which take you into the Western edge of Longmont, CO, home to 2 famous craft breweries: Left Hand Brewing and Oskar Blues Brewery.

From there you'll wind your way through neighborhoods before heading West on @slice[17th Ave](d,90297.07,93493.05) back to Hygiene at 58 miles. Great time to take another break to refuel and fill water bottles at @poi[Mary's](2476003). You'll then continue South on @slice[75th St](d,93493.05,99910.99), @slice[Plateau Rd and 73rd St](d,99943.64,103173.51) to the edge of Niwot, home of Thule's Western US distribution center.

West on @slice[Niwot Rd](d,103165.77,105229.3) and South on @slice[63rd St](d,105229.3,108619.9) takes you into Gun Barrel, CO, home of the Avery Brewing Company. Heading East on @slice[Jay Rd](d,111314.1,115340.4), you will enjoy a spectacular view of the Flatirons range outside of Boulder in the distance. The entire length of Jay Rd is a long false flat leading up to the Northeast part of Boulder. Take heart, the ride is almost over and you'll enjoy the rest of the ride through some nice neighborhoods before winding up back in downtown Boulder. As you turn right from 13th St onto Spruce St, take note of the historic @point[Boulderado Hotel](d,120258.69) on your right - It's a beauful old (but pricey) place to stay, just a block North of the Pearl St Mall.

One more turn South on 9th St takes you back to @poi[University Bicycles](2476002) and the end of your trip. I've done this ride several times and it's definitely in my top 10 best. After your ride, head just a block down the street to @point[Spruce Confections](d,134.18), a local sweetery, coffee shop and cycling hangout. If you're in the mood for something stronger, it's a short walk West to the Pearl Street Mall. There are too many bars and restaurants to mention, but a few I can recommend include The West End Tavern, The Kitchen Bistro, West Flanders Brewing Company, The Lazy Dog Sports Bar, Illegal Pete's and Pizzeria Locale, all located on Pearl Street.

# Links to points of interest
* [University Bicycles](http://ubikes.com/)
* [Downtown Boulder - Pearl Street Mall](https://www.boulderdowntown.com/visit/history-of-pearl-street)
* [Carter Lake Reservoir](http://www.co.larimer.co.us/parks/carter.cfm)
* [Boulder's Flatirons](https://en.wikipedia.org/wiki/Flatirons)
* [Left Hand Brewing Company](http://lefthandbrewing.com/)
* [Oskar Blues Brewery](https://www.oskarblues.com/)
* [Avery Brewing Company](https://www.averybrewing.com/)
* [The Boulderado Hotel](http://www.boulderado.com/)

# More resources

Interested in more rides in the Boulder area? While I'm no expert on the area, I've ridden there a lot. Feel free to look over and use my other routes:
* [RwGPS Boulder Rides](https://ridewithgps.com/events/11145-boulder-rides)

# Important Reminders

This is a long and challenging ride with lots of climbing on sometimes secluded country roads. Other than at the start and end, there are no bike shops and limited places to stop for water or food. Carry at least two water bottles, gels or snacks, cell phone, tools and tubes in the event you have mechanical issues. In my experience, this route is good for riding any day of the week. Be sure to bring a camera - everywhere you look is a picture in waiting.

Boulder to Carter Lake Loop

Route Overview

Route Details

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