The Bitterbrush and Nelson Loop Trails are fairly difficult mountain bike routes that form a lasso trail near Lyons, CO. Unlike many of my other trail guides, this one is definitely a little more strenuous and technical. If you are riding a bike, prepare for steep climbs and rapid descents. There are some tricky corners and numerous rocks and roots in the trail. There is also great scenery, lots of wildlife, and a heck of a roller-coaster ride. Although this trail is good for hiking, many hikers choose Nighthawk Trail, which runs off of this trail and takes a similar route. HISTORY: In 1885, Edward Lyon settled the land that later became Hall Ranch. The sandstone quarries just to the east of Hall Ranch are made up of 52 smaller quarry pits, and these were also established by Edward Lyon. Electricity was first introduced to the region around 1912 when the Longmont Aqueduct, which supplied water from Longmont Reservoir to the power plant, can still be viewed on the north side of Hall Ranch. The name Hall Ranch was first applied to the land in the early 1940s when Hallyn and June Hall purchased a chunk of the surrounding land. WILDLIFE: Hall Ranch is rich in wildlife. It is considered a crucial nesting habitat for numerous birds. Predatory birds such as golden eagles hunt here and are always on the lookout for a feast of prairie dog or squirrel. White tailed deer and rabbit are also commonly seen from the trail. One of the better places for observing wildlife at Hall Ranch is in the meadow at the junction of Bitterbrush and Nelson Loop. In addition to the cute and cuddly critters, don't forget that rattlesnakes love sunning themselves on the trail. Leave them alone, and they're usually pretty docile. GEOLOGY: The oldest rock in the area is about 1.7 billion years old and the youngest is approximately 62 million years old. The rocks are a mix of sandstone and granite.