There are a lot of different flavors of suffering. A bunch already tossed out, but I'll add a different type of spice--not just the terrain, but the vegetation and weather.
Have spent a lot of time backpacking and climbing in CA,OR, WA, UT, MT, WY, CO, NV, AZ, NM for comparison. They are all "more rugged" in many ways than the place I'll throw out, but at the same time nearly all can be much easier in other ways. Northern NY/New England higher-elevation mtns--the adirondacks, greens, whites, etc--near treeline, which is at about 4000' and is the same vegetation-type as you'd encounter at like 11,000'+ in the rockies, can be ass-kickers. Generally not as steep as younger mountains, but the krumholz--locally known as "cripple-bush"--is thick and healthy and trying to bust through it is "character-building". I've found some similar stuff in the Wrangells in AK. Here, we sometimes cut or follow buck tracks through this zone near treeline, and between the moss-covered rocks (or should I say the bottomless holes between the moss-covered boulders), fighting through the wet, snow-covered brush until you're drenched and clothes are full of holes, and the typical weather pattern we hunt it in (increasingly crappy and wet weather followed by a sudden temperature drop to well-below freezing), and in minutes you can literally go from a blissful afternoon in the hills, to dying from hypothermia in the middle of nowhere. There is a reason the climate in this area is technically called "arctic maritime".
Have spent a lot of time backpacking and climbing in CA,OR, WA, UT, MT, WY, CO, NV, AZ, NM for comparison. They are all "more rugged" in many ways than the place I'll throw out, but at the same time nearly all can be much easier in other ways. Northern NY/New England higher-elevation mtns--the adirondacks, greens, whites, etc--near treeline, which is at about 4000' and is the same vegetation-type as you'd encounter at like 11,000'+ in the rockies, can be ass-kickers. Generally not as steep as younger mountains, but the krumholz--locally known as "cripple-bush"--is thick and healthy and trying to bust through it is "character-building". I've found some similar stuff in the Wrangells in AK. Here, we sometimes cut or follow buck tracks through this zone near treeline, and between the moss-covered rocks (or should I say the bottomless holes between the moss-covered boulders), fighting through the wet, snow-covered brush until you're drenched and clothes are full of holes, and the typical weather pattern we hunt it in (increasingly crappy and wet weather followed by a sudden temperature drop to well-below freezing), and in minutes you can literally go from a blissful afternoon in the hills, to dying from hypothermia in the middle of nowhere. There is a reason the climate in this area is technically called "arctic maritime".