* Distances may look short on the map but the situation on the ground may be much more difficult. It takes a lot of time and sweat to travel any distance over rough, rocky, heavily wooded terrain. More so if you carry a lot of gear. Never underestimate the terrain and always plan your route realistically.
This is soooo true. People seem to believe they can travel faster than is realistic when wearing a pack, and covering uneven terrain, up and downhill. When we plan hikes with youth, we use a pretty simplistic rule of thumb, estimate 2 miles per hour, add an extra 1/2 hour for every 500-1000 feet of elevation change, depending on just how severe it is. (If the contour lines start looking like the grooves on an LP, it's getting more like rock climbing!)
I forget where that rule of thumb comes from. Some people say start with 3 miles per hour, which is ok for fit athletic individuals, but, as the trip leader, you have to plan with your slower hiker setting the pace. It's not bad to arrive early, but, bad things happen when you're later than expected and still out on the trail.