My 5 year old daughter and I took the dublin trail to Monadnock summit. We ended up clocking 5.1 miles with 1700 feet of elevation gain. Gorgeous hike that has a bit of everything. The first mile and a half or so was below tree line and featured a stream that runs alongside with a few intersects. We went the day after some heavy rains, so the trail was quite wet and muddy. My daughter loved the scrambling (theres a lot) especially as you get closer to the summit. This trail is definitely moderate with no sections that would qualify as dangerous for kiddos. This is a great first big mountain climb for young kids. As expected the summit was quite crowded, but we only encountered about 7 other groups on Dublin itself.