Seal Mountain Trail has only one trailhead, so you're looking at an in and out backcountry hike. The total elevation difference for this great outdoors hiking trail is 1,485 feet which is about average. The great outdoors trail stays roughly within the same elevation zone the whole time, so you won’t have to worry about different climate zones along your backcountry walk. This great outdoors hiking trail is not that long but you should still bring some emergency supplies just in case something happens. You should count on this hike taking about 4.5 hours, but you never know stuff could go wrong and you could get stuck so be prepared for that. This neighborhood does get very dry sometimes, so make sure you check current conditions and fire restrictions with local forest authorities before you head out. Being 5.4 miles long it's a mid length backcountry walk.