Answer
The architect behind Urbino's magnificent Cathedral (Duomo) was Francesco di Giorgio Martini, a prominent figure of the Italian Renaissance. Martini, known for his versatility as an architect, engineer, and sculptor, left an indelible mark on the city. The Duomo, with its elegant façade, intricate carvings, and harmonious proportions, stands as a testament to Martini's exceptional talent and enduring influence on Renaissance architecture.