Road-biking Denver's Northern Suburbs, Part 4: Rocky Mountain Arsenal

For much of the latter half of the 20th century, the Rocky Mountain Arsenal was a site for the manufacture and storage of chemical weapons. In more recent years, it has been converted to a wildlife refuge. It features a nice visitor's center with activities for children and some walking trails.

The fourth cycling route in this series is a loop around the Rocky Mountain Arsenal lands and its surrounding rural and suburban areas.


View Rocky Mountain Arsenal Loop in a larger map

This is a ride I like to do early on a Sunday morning. A major reason for that is SH2 (the diagonal road on the map) is not a good cycling road. It has no shoulder and can have quite a lot of industrial Commerce City traffic. But on a Sunday morning, while everyone else are still in their slippers and drinking coffee, the roads are almost empty and even highway 2 isn't so unpleasant.

The route begins at the park next to Themmig Elementary School, just off of Peoria Street. From there, head south on Peoria, take a quick left on 104th Ave, and then right on SH2. South of 96th Ave, the Rocky Mountain Arsenal flanks the road to the East.

Turn left on Quebec Pkwy (called Rosemary Street when turning right). My experience has been that Sunday morning traffic on Quebec is actually heavier than on SH2. But the road is much wider, so it still feels safer. There is a convenience store at the corner of Quebec and 72nd Ave, should you need any refreshments.

56th Ave starts out as a sub-par biking road as well. Dick's Sporting Goods Park can tend to bring in a lot of traffic, but that doesn't last very long. Soon traffic dies down and the road widens, and you're rolling along with the open lands of RMA on your left. A left-hand turn onto Havana would take you to the RMA visitor's center.

Heading north on Tower Road, you will soon come to a cluster of hotels and restaurants which serve some demographic related to Denver International Airport. Presumably there is a demand for these places, but it seems like an odd location to me. Farther up the road, around 104th Ave., is the community of Reunion. There are some businesses around that intersection, probably including a convenience store, but I've never looked closely enough to be able to say exactly what you'd find if you were to turn in there.

At 120th Ave, the RMA route overlaps with the Adams County Loop, so you could keep going on Tower Road and head up toward Brighton. Turning left on 120th takes you westward, back to Peoria and the beginning of the loop.

The beginning and ending point on Peoria is presented here because it's the closest public parking I've found for those who might be driving to get there. But when I'm approaching this loop by bike (heading east on 120th), I actually prefer to take Chambers to 96th Ave, and then head west to get back to SH2. That reduces the amount of time spend on the highway and increases time spent along side the Arsenal. This alternate route is marked in purple in the map above.

Road-biking Denver's Northern Suburbs:

• Part 1: Adams County Loop
• Part 2: Thornton, Erie, Dacono
• Part 3: Thornton, Dacono, Fort Lupton

Road-biking Denver's Northern Suburbs, Part 3: Thornton, Dacono, Fort Lupton

This third route in the "Road-biking Denver's Northern Suburbs" series is another loop through the farm lands north of the suburbs.


View Thornton, Dacono, Ft. Lupton in a larger map

The route begins at the ball fields on Holly Street, just south of 136th Ave. There is ample parking available, and it's a good spot to meet up with friends if you're going for a group ride. Construction is currently in progress to extend the complex with a skate park. There are several opportunities along the route for picking up snacks and drinks.

From Holly Street, go north and take 136th Avenue east to Colorado Blvd. From there, it's a long, straight shot up to SH 52. As you approach Dacono, the blue water tower just south of the highway becomes visible. Here we intersect with the Thornton, Erie, Dacono Loop from part 2. Combining the two makes for a nice, longer ride.

Colorado Blvd, south of Dacono

As in part 2, SH 52 is higher traffic than the rest of the route, but it's fairly moderate, at that. Heading east, the shoulder varies and is rough in places, but it's rideable throughout.

Just before Fort Lupton, you will cross the South Platte River before the underpass at US-85. Ride through town, through a couple of traffic lights, and turn left on what is variously known as Business US-85, County Road 27, or in these parts, South Denver Ave.

South Platte River, Fort Lupton

As you come near to Brighton, there is a large factory where wind turbine parts are manufactured. Sometimes the huge blades will be loaded onto railroad cars, ready for delivery.

The intersection at 168th provides another chance to extend the ride by heading east and following (in reverse) the Adams County Loop described in part 1.

Heading west on 168th Avenue, you will cross back over the river, past a concrete loading site, and then turn left onto Tucson. Here, and farther on Riverdale, there are some sand quarries which provide some large truck traffic, but I've never found it to be a problem.

From Tucson, turn right on Highway 7, or 160th Ave. Then take the first left onto Riverdale, just before the hill. The stretch along Riverdale is quite pleasant. At the stop sign near the golf course, turn right onto 128th, leading back to Holly Street and the end of the ride.

Road-biking Denver's Northern Suburbs, Part 2: Thornton, Erie, Dacono

This is another of the routes I like to ride in the morning before heading off to work. It quickly takes you out of town, past some of the outer subdivisions, and into the rural countryside. On clear mornings the view of the mountains out to the west is quite nice.


View Thornton, Eerie, Dacono in a larger map

I usually ride this loop clockwise, if only because the right-hand turns are easier to make. The map shows the ride beginning and ending at the parking lot of the shopping center at 136th and Colorado Blvd, but as with the first installment of this series, it is easily accessible from most of the northern Thornton area.

There is a landfill at the northern end of Sheridan Parkway which results in a little bit of extra traffic from garbage trucks. But it isn't bad and doesn't detract from the enjoyment of the ride.

It is common to see hot air balloons in the sky to the west as you ride north along County Road 5, and the view of the mountains is usually very nice. That road takes you past Erie High School, an airstrip community, and a salvage yard for old VWs. The route then turns onto SH 52 just before the county road turns to gravel.

SH 52 is the highest-traffic road on this route, as it is an I-25 tributary, but the shoulders are pretty good, and even at the intersection with the interstate, it is quite manageable. There are a couple of convenience stores accessible from this point - one near I-25 and the other just past the turn onto Colorado Boulevard, also known as Weld County Road 17 in these parts.

I like to note the four radio towers on the east side of the road just north of 168th Avenue, or Baseline Road, which serves as a good distance marker as you head south. Shortly after that is the intersection with 160th/SH 7, and then the home stretch back to the beginning.

Road-biking Denver's Northern Suburbs, Part 1: Adams County Loop

The Joy of Wide-open Spaces

The plains which surround the Denver area to the North and East are not touted as much as the foothills and mountains to the West as prime road-biking territory. But what the plains lack in steep grades, switchbacks, and majestic canyon walls they make up for in sweeping vistas, low-traffic roads, and the rural farming communities which I feel are quintessential of the American West.

For those of us who live in Denver's northern suburbs, these plains are our stomping ground for daily riding when schedules do not allow for an hour of driving just to get to a decent hill to climb. In this series of posts, I will present some of the routes I like to ride in this area, which generally strike out from Thornton and tour the back roads of this region.

Adams County Loop

This is a 20-mile loop that I discovered a few years ago which has become a staple on days that I just want to get out for a little while for a quick ride. Parts of the route also lend themselves to doing intervals, if you're looking to get more of a workout. There isn't much to recommend one direction over the other, but for some reason I usually go counter-clockwise.


View Adams County Loop in a larger map

This shows the ride beginning and ending (the bicycle icon) at a parking area near the Adams County Regional Park, but it is easily accessible by bike from most areas in Thornton, Brighton, and perhaps Northglenn. If you begin by heading east, there are a few stop signs and traffic lights early on. Once on Tower Road, the ride is uninterrupted until you get to 152nd/Bromley Lane.

168th Avenue features a little bit of a grade, going uphill for a short way before heading downhill toward US-85. At the intersection of 168th/Baseline and US-85, there are service stations, should you need to pick up additional drinks or snacks.

Riverdale Road is another good stretch without traffic lights or stop signs. I often use Riverdale as a convenient place to do intervals. There is a sand quarry midway along the road, so there are some big trucks going through there. But the traffic is still quite sparse and generally polite. I regularly see wild turkeys in the horse pastures along Riverdale, which always adds to the interest of the ride.

As will be seen in future installments, this route can easily be extended to increase the mileage.