BIRKENSTOCK SIENA sandals size 38. Preowned n excellent condition, worn just once. Some wear as seen in photos. In khaki/gold suede. The BIRKENSTOCK Siena boasts a refined appearance. Crossed straps give the sandal its unique and special look. Featuring a tonal footbed and outsole, the footbed is also fully wrapped in luxurious suede. The upper is shown in a soft, metallic suede.