Mount Jefferson, named after the third U.S. President, is the third highest peak in New Hampshire, in New England, and in the Northeastern United States. It is located on the main Presidential Range crest between the first and second highest peaks--north of Mount Washington (and its northern outlier Mount Clay) and south of the bulk of Mount Adams. Located at the center of the scenic Northern Peaks of the Presidential Range, it, like its neighbors, boasts a vast area of rare eastern above-timberline terrain, and weather that can rapidly become near-Antarctic.
Given its position, Mount Jefferson could easily be overshadowed by its neighbors, but the peak has more than enough interesting features to give it a personality of its own. Two pinnacled ridges, the Ridge of the Caps and Castle Ridge, drop off to the west, and the double "knees" of Jefferson are two short ridges that fall very precipitously down to the huge gorge of the Great Gulf. Jefferson Ravine and Castle Ravine are two large, classic glacial cirques on the mountains flanks, and just south of the summit the broad, grassy expanse of Monticello Lawn breaks up the monotony of talus blocks that cover most of the upper mountain. The summit area has three little peaklets in a triangle, and is possibly the best viewpoint in the Presidentials, with Adams, Washington, and the Great Gulf all visible close-up.
Jefferson is also the only 5000-footer in the Northeastern U.S. (outside of Washington with its road and train) that can be climbed with less than 3000 feet of vertical gain, using the Caps Ridge Trail from Jefferson Notch. This trail, though, is steep and very rugged as it traverses the "Caps", little knobs of rock, and it is best avoided by novice hikers. Even steeper is the notorious Six Husbands Trail up from the Great Gulf, which frequently resorts to ladders to climb the north knee ridge. The gentlest ways to gain Jefferson's summit is to use the Gulfside Trail (and its summit loop), a segment of the Appalachian Trail that threads all of the Northern Peaks. In my opinion, the Gulfside is the single nicest walk in the entire eastern U.S., but is very difficult to do as a day hike.