HD 310 covers the Upper Gallatin Canyon and the mountains between Big Sky and West Yellowstone—country that ranges from ski resort development to genuine wilderness in a matter of miles. Elevations run from about 5,500 feet on the Gallatin River near the mouth of the canyon up to 11,000 feet on the peaks of the Madison Range and the Spanish Peaks. The canyon itself is narrow and steep-sided, with the Gallatin River cutting through a mix of open meadows and dense conifer forests. The west side climbs into the Lee Metcalf Wilderness and the Spanish Peaks, which are rugged granite and metamorphic mountains cloaked in spruce-fir and lodgepole. The east side pushes toward Yellowstone National Park, and elk move freely across that boundary—a fact that defines the hunting here. The HD is a mix of Gallatin National Forest (now Custer-Gallatin NF), Lee Metcalf Wilderness, and private land, particularly around the Big Sky Resort area. US-191 runs the length of the Gallatin Canyon and is your primary access; forest roads branch east and west into the side drainages. The Big Sky area has full resort services at resort prices. West Yellowstone has gas, groceries, and lodging and is a popular base camp. Cell service is good along US-191 and dies in the backcountry. This HD is famous—or infamous—for the Yellowstone boundary elk situation: large herds that summer in the park and migrate north and west into huntable country when snow pushes them. Late-season hunts can produce incredible numbers, but the timing depends entirely on weather. The combination of wilderness, rugged terrain, and park-boundary dynamics makes this a complex HD that rewards hunters who understand elk migration patterns and aren't afraid of deep snow and cold temperatures. HD 310 (upper Gallatin Canyon / Big Sky to West Yellowstone) is famous for the Yellowstone boundary elk dynamic — large herds that summer in the park migrate north and west into huntable country when snow pushes them. General elk tags are available OTC for residents; some late-season permits are limited entry. The Lee Metcalf Wilderness and the Spanish Peaks provide rugged backcountry, and Custer-Gallatin National Forest covers most of the HD. Private land around Big Sky Resort limits some valley-floor access. Bull-to-cow ratios are moderate but variable depending on migration timing. Block Management is limited. The late-season hunts can produce incredible elk numbers, but timing depends entirely on weather — if deep snow does not push elk from the park, the hunting can be slow. The combination of wilderness, rugged terrain, park-boundary dynamics, and unpredictable migration makes this a complex HD that rewards hunters who understand elk movement patterns and are not afraid of deep snow. Grizzly bears are present throughout — carry spray. West Yellowstone and Big Sky provide staging options at varying price points.