Here in southern Ontario we have a small city called Stratford. The river that runs through it is the Avon-- though our Avon flows into the Thames (which runs through London) :-P
Anyway, back to Stratford. Our Stratford is known for... Shakespeare. Of course he wasn't from this Stratford, but the town has a big summer theatre industry that attracts actors (and sometimes audience members) from far and wide, and although it now features all kinds of theatre, it started out as a Shakespearean festival.
The festival's first performance was a production of Richard III staged in July of 1953 with Sir Alec Guiness playing the title role. Although the festival built an impressive stage and amphitheatre of poured concrete, those elements didn't have a building around them, so the first several seasons' performances were held beneath a huge circus tent. When the theatre building was eventually built, the shape of a circus tent was incorporated into the design in tribute to the festival's early days.