Stob Biorach

The walk up Stob Biorach is steep, relentless, and absolutely worth the sweat. This 901-metre peak sits above Loch Lomond near Alexandria, and from the summit you get proper views across the water to the bigger mountains beyond - Ben Lomond dominates the view to the south. The ascent takes about ninety minutes if you're fit; allow three hours for a round trip with time to catch your breath at the top.

It's a walker's mountain rather than a casual stroll. The path climbs through woodland at first, which is pleasant enough, then opens out onto rougher ground where the gradient really bites. Boots are essential - trainers will leave your feet sliding on loose scree near the top. You'll see proper hillwalkers and families with older kids, but younger children would struggle with the elevation gain.

Start early. The car park fills quickly on weekends, and the weather turns fast up here - what looks clear from the village can be thick cloud by noon. Conditions in winter make this a serious undertaking.

If you're based at Inverbeg Holiday Park or Milarrochy Bay, both just a few miles away, this works as a half-day expedition that won't bore teenagers. The views reward the effort - you can see why people come back to Loch Lomond year after year. Free to climb, obviously. Just bring water and proper kit.