From its northern terminus in Maryland headed south, the range is composed mainly of a single north-south running ridge with periodic low-lying gaps, though it does contain several spur ridges, most notably near its intersection with South Mountain at its northern terminus. Its ridge character continues south of the Potomac in northern Loudoun County, losing elevation, until just north of Leesburg, where the range widens into a broad plateau of undulating hills separated by deep stream valleys. The range reaches its widest point north of Goose Creek at nearly three miles. South of the creek the Catoctin vanishes into the Piedmont countryside near the northern terminus of the Bull Run Mountains at Aldie.
A hiking trail, the Catoctin Trail, traverses the northern half (almost 27 miles) of the range. It is maintained by the Potomac Appalachian Trail Club.
The trail starts at Gambrill State Park, which contains several shorter hiking and mountain biking trails as well as picnic pavilions, and continues north to Cunningham Falls State Park and Catoctin Mountain Park. Both parks contain many shorter hiking trails and organized campgrounds.
The Catoctin Mountain Byway, a Maryland Scenic Byway, loops and weaves through the northern part of the range.
The name of Catoctin Mountain follows the convention of referring to an entire mountainous ridge as a single "mountain" in situations where there is no single prominent peak. Nevertheless, it is still occasionally called the "Catoctin Mountains."
According to the USGS, variant names of Catoctin Mountain include Kittochiny Mountains, Kittockton Mountain, Kittocton Mountain, and South Mountain. However, in Maryland, South Mountain and Catoctin Mountain are separate, roughly parallel, mountains.
The portion of the ridge directly west of Frederick, Maryland is known locally as Braddock Mountain, although the name is not recorded in the federal Geographic Names Information System. (The GNIS does, however, recognize the community of Braddock Heights, which is located on the ridgecrest at this point.)
Much of the mountain, being shattered rock, is home to large populations of timber rattlesnakes. There are also black bears, turkeys, deer, as well as vultures and raptors.
Catoctin Mountain is best-known as the site of Camp David, a mountain retreat for presidents of the United States. It was first used by President Franklin D. Roosevelt in the 1930s, who called it "Shangri-La". In the 1950s President Dwight Eisenhower renamed it Camp David, after his grandson David Eisenhower. The resort is extremely well-guarded by the United States Secret Service, and only approved guests of the President are allowed into the retreat. Due to its proximity to Washington, DC, and its beautiful mountain scenery, Camp David has proven to be a popular weekend "getaway" for many United States presidents, and approximately 1/3 of Catoctin Mountain Park can be closed to the public on short notice, such as the July 10, 2008, press release announcing that the park would have multiple closures starting starting Friday, July 11th through the following Sunday.