The Guinness Book of Records lists The Olde Fighting Cocks in St Albans Hertfordshire as the oldest pub dating from 1539. However, there are at least two other pubs which claim to be older. Their problem is that they can't prove it.
The Old Wellingtonian is reported to be the oldest pub in Manchester
The oldest pub in Scotland is The Sheep Heid Inn, Duddingston, Edinburgh.
The oldest pub in wales is The Skirrid Mountian Inn, in a small village near Abergavenny in Monmouthshire.
Royal Albion
king's head
J D Wetherspoon's owns the largest pub in the UK, The Regal in Cambridge.
The Bell Inn Finedon Northants 1042.
king's head
The Hope and Anchor is the oldest continually licensed pub in Australia, opening its doors on July 25, 1807 under the name of the Whale Fishery
Queen's Head in North Adelaide
Unconfirmed but very possibly Sean's Bar in Athlone, Ireland. It is already recognised as the oldest in Europe.
Ye Hole In Ye Wall, Est. 56BC