@Fubar - you're right - there are not enough 100km audax events around the central belt

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160km 3 Glens Explorer is a good ride - I've done it a couple of times. The only tricky bits are the short (~500m) double-chevronned

uphill just after passing the road to Path of Condie - and the sharp right-angled right bend on the very fast descent in to Dunning. A couple of people came off here in the wet one time ....
Glen Devon is a long steady ascent and the downhill is great - until you remember you have to turn right and go the back way to Auchterarder !
I'd wanted to do it again last year but had cold feet and not enough 'bent miles in the legs.
Hmmm .... 3 Glens this year ...