An Caisteal (The Castle) is basically a knowlly peak at the end of a long ridge known as Twistin Hill. It is located just south of Crianlarich, Scotland.
The Twistin Hill ridge begins once reaching the top of Sron Gharbh, which stands at 709m. The long narrow northern ridge steepens gradually until reaching the summit of An Caisteal at 995m.
The path along the ridge is fairly well defined although attaining the start of the ridge requires negotiating your way through thick grass and peat bogs.
Approx time: 5 Hours
For those wanting to add another munro peak onto the day, the peak of Beinn a' Chroin can be done. This peak will add roughly 1.5 hours onto your day.
From Glasgow take the A82 road via Loch Lomond direct to Crianlarich.
Crianlarich can also be accessed from Stirling, Perth or Edinburgh by joining the A85 road or from Fort William by joining the A82 road southbound.
Parking is available at the layby opposite Keilator Farm.
Start at the parking layby opposite Keilator Farm.
Climb over the style and head towards the railway bridge. Pass underneath this and follow the dirt track up for roughly ten minutes until deciding to veer south-west in the direction of Sron Gharbh. There is no defined path for attaining the top of Sron Gharhb so you just need to go for it. The lack of a path makes this slightly heavy going especially on the legs, but probably accounts for the fact there are very few other groups out on the hill.
On reaching the summit of Sron Garbh follow the path leading south along the ridge known as Twistin Hill. The path is a good one and gradually steepens until encountering a small degree of scrambling at one point where a large pot hole in the path appears. This is a pretty large pot hole!
Continue onwards until reaching the first cairned summit. This is not the true summit and a further five minutes walking will take you to the true summit.
For the continuation onto Beinn a'Chroin follow the path leading from An Caisteal south then south-east down to Bealach Buidhe. Once at the lowest point between the two peaks, bear east over the crags onto yet another false summit. Continue east along the path until reaching the true summit.
Summer conditions: Backpack, walking boots/trainers, hat, gloves, water, food, waterproofs(your in Scotland you can bet it is going to rain at some point), map, compass, first aid kit, penknife, spare socks, walking poles can be good to ease the jarring on the old knees and your camera.
Winter conditions: All of the above and ice axe, crampons, helmet and rope.