Do the top loop of the trail anticlockwise and as you emerge from the trees follow the ridge up to the right. We later met a local lady running it who said it was fine to continue on up that ridge and on round to the left across the top of the short valley on an obvious path and on further to the top of the Opal Hills. She then advocated the scree run down the front of the mountain to rejoin the marked trail and continue round the loop.
We'd only ventured up the first part of the ridge off the trail - but even that was worth it for the views and a nice spot for lunch.
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