My POTM could have been any of these, really - all excellent in their own way:

Croydon - Green Dragon
Edinburgh - Abbotsford (New Town), Bennets (Tollcross), Cloisters (Tollcross), Doric (Old Town), Holyrood 9A (Old Town)
Foxton - Bridge 61
Glasgow - Bon Accord (Charing Cross), Counting House (Central), Three Judges (Kelvinhall)

but I'll go for The Holyrood 9A because it was such a surprise, discovering an unreviewed bar with 20 beers on tap (albeit 16 being of the craft keg variety) having popped in on the off chance as I was passing...