Horse And Trumpet

Run by the Grand Union Folk Club on the first Monday of the month from 8pm to 10.30pm (ish)
Mostly English tunes, but tunes from the rest of the UK, Europe or even further afield can be included.
The music sessions are open to any musician who enjoys playing folk music. While the music tends to have a bias towards the tradition, the format is reasonably free and the actual tunes played on any given night are collectively determined by those taking part. The sessions start at 8.00pm, there is no entrance fee and the pub keeps a good cellar with real ales always available.
See the Grand Union Folk Club website on https://guf.org.uk/