If it's any point of reference for my conditioning level, I hiked the trail that circles Jordan Pond in Acadia National Park in Maine (near Cadillac Mountain) in 1.5 hours in 2018. That is a 4 mile trail over flat but irregular terrain that varies from a dirt path to stepping over rocks, to wooden boardwalks in places. You are slowed down by the areas where you are climbing over rocks. Granted it was flat, but I had no problems with it. There are no restrooms on the actual trail, but at the very end of it there is an information center with a restaurant and restrooms.
That Jordan Pond hike I did alone. I remember seeing a lot of the small red squirrels that are prevalent in Maine. They make strange noises and a few times they startled me. I saw no other wildlife although there is bear and moose in that area.