The old Italian city of Siena lies upon three hills, on one of which gleams the great white Cathedral, and on another perches the scarcely less commanding Church of San Domenico. In the fourteenth century underwood and hanging gardens crept up the sides of these hills, with only a narrow winding road to lead from one part of the city to another. The valley lying between the two hills that were crowned with churches was known as the Valle Piatta, and a little way up one slope stood the small stone-built house of a dyer named Giacomo Benincasa.