We hiked up Mt. Willard from the AMC Highland Center in Bretton Woods. You literally walked across the huge field that's in front of the lodge and there's the hiking trail. It's a fairly easy hike with lots of greenery and boulders along the way. My kid was 1.5-years-old when we did this short hike and he walked a good amount of it at the beginning and then some at the end when it was a bit more flat. In between he was in a carrier since it got a bit steep. When you get to the top you'll have a great view down the valley from the huge boulder that's Mt. Willard. This is an excellent hike for kids 7-12, as they should be able to walk the 1.5-hour hike without much trouble.