Yes, its tempting to park opposite the turn round at the end because it looks more level, the local bus service no longer runs, but coaches and lorries do often use this. Its getting to be a very popular spot for motorhomes in holidays and at weekends when Castleton, Mam Tor and surroundings are seething. I think its only a matter of time before we lose this one, unfortuneatly too many vans don't give a b*****r, park all over the turning space and act like happy campers...or in some cases happy crappers. There is meter parking lower down the road (well the few un-vandalised meters anyway). The meters only function weekends and bank holidays, so likelihood of parking wardens is probably low during the week, especially at night.
Do you mean the Anglers Rest in Bamford? If so be aware the carpark is not very level, also since it's Easter the pub will be busier than usual and motorhomes may be difficult to accommodate...ring ahead to check. The more popular car parks in the area do fill up rather quickly at this time of year, but there is a quiet parking area on the minor Yorkshire Bridge to Thornhill road known mostly by local doggy walkers...a bit sloping except at the upper end.
If the other Anglers Rest in Millers Dale... the car park is not very large and it's a popular spot during holidays, again I'd ring and check.
We live in this part of the Peak District...and generally avoid going anywhere locally in the car during the day at weekends and especially public holidays, too much traffic and car parks full (especially the free ones)...during the week its refreshingly peaceful. But its a small price to pay to be able to go walking in such lovely countryside right from our doorstep.