From the top car park take the track downhill, where it soon crosses the Burn of Care before looping back towards Castle Campbell. At the castle entrance sign go right onto a footpath that climbs towards the Burn of Sorrow, then follows it upstream through the woods above the gorge and waterfalls. Cross to the south bank of the burn at a footbridge and continue uphill onto open ground overlooking the castle. Above is Bank Hill. This can be skirted on the right, but it's hardly worth avoiding and has a good view over Dollar.
From the cairn on top go over the next little summit, cross a saddle and continue up the southeast flank of King's Seat Hill, passing over an unusual series of terraces and gullies (the result of a landslip maybe?). A long steady ascent brings you to a memorial cairn for a WWII air crew. Just beyond is the cairn and stone walled wind break on the broad summit. This is a great viewpoint, taking in a huge sweep of country - the Lomond hills, the Pentlands, the Forth valley, distant peaks of the Highlands ...and industrial landmarks from Rosyth's dockyard and the steaming stacks of Grangemouth to the Burnfoot Hill wind farm (which does a reasonable job of spoiling the Ochils' northern flank).
Looking west from Ben Cleuch© Dan Bailey - UKHillwalking.com, Oct 2012
Head roughly west in descent, soon bearing right off the well-trodden path to reach a col at the head of the Gannel Burn. Cross a fence, and continue west(ish) up Andrew Gannel Hill - there's a path on the ground, though not on the map. The path follows a fence line for the short descent off Andrew Gannel's west side, and on up towards Ben Cleuch. At a fence junction above The Law meet the better-used Tillicoultry-Ben Cleuch trail, which leads - via some boggy bits - to the high point of the Ochils.
Retrace your steps onto Andrew Gannel Hill, then bear roughly northeast to follow a less-trodden path that runs beside the fence down to the boggy saddle at Maddy Moss.
Stay with the muddy path/fence over Skythorn Hill, then traverse the southern flank of Cairnmorris Hill to the col to its east. Squeeze through a new gate in a deer fence, then climb quite steeply onto Tarmangie Hill.
A wall-and-fence and an obvious path now lead on to Whitewisp Hill, the last summit of the round. Just beyond the summit cairn start bearing right, where a path (of sorts) descends the hill's southern flank onto the little spur of Saddle Hill. Coming off this the trail tends to disappear, so just ad-lib your way down a steep grassy slope (small crags - nothing to worry about) to the shallow-angled sheep pastures below. Rough ground leads to a point overlooking Casle Campbell and the woods of Dollar Glen. Meet a little path at right angles here, and follow it leftwards back down to the castle access track not far from the car park.
Castle Campbell, Dollar© Dan Bailey - UKHillwalking.com, Oct 2012