Siena is a city where the architecture soars. Effectively a giant, open-air museum celebrating the Gothic, Siena has religious and secular monuments that have retained both their medieval forms and their extraordinary art collections. Often referred to as Florence’s longtime rival, this city of rose-coloured brick seems to have come out on top in terms of a more unified preservation and grace. With steep, twisting stone alleys and churches, palaces, and crenellated public buildings draped across its gentle hillsides, Siena is for many admirers one of the most beautiful towns in Italy. It’s a feast for the senses and an…