I thought I knew a lot about the Stiperstones, but thanks to a tweet from Wild About Walking I made a new discovery today.
There is an Orthodox monastery in the Eastern shadow of these hills.
The website of the Monastery of St Antony and St Cuthbert says:
There is no access to the Monastery by car. The farm track is long and rough. The nearest Car Park is at the Stiperstones Car Park at the Knolls, which is a 45 minute walk along the hill below the Stiperstones.