Stratford-upon-Avon is an historic town on the River Avon in the English county of Warwickshire, best known as the home town of the great English playwright and poet, William Shakespeare. Today, it is a major theatre-going destination as the home of the Royal Shakespeare Company. As such, it represents one of the most popular tourist destinations in the country.
Although it's often abbreviated to just "Stratford", when organising transport or accommodation always refer in full to "Stratford-upon-Avon". There's a large district of London called Stratford, where you don't want to go by mistake.