The Circus Tavern is located on the north side of Portland Street close to the junction with Princess Street.  I found this description of The Circus Tavern on  the "dooyou.co.uk" website.  "The Circus Tavern is reputed to be the smallest pub in Manchester and also one of the smallest in the UK. Records also say that it is a very old pub ~ it was built around 1790 and was the place where circus performers and entertainers from the Chatham Street Circus (a street near to Portland Street) would meet for a few drinks."