Hotel Number Nine Spa

The spa of Hotel Number Nine, a family-owned five-star boutique hotel on Via dei Conti near the Duomo and the Medici Chapels, has a sauna, a Turkish bath, a cold tub, a hydromassage tub and a relaxation room with a 4K home theatre. Treatments include Chinese reflexology baths. The website does not say whether non-guests can use the spa, so ask reception.