📜 Magnificent 18th-century Rococo library within the Royal Building of Mafra, a UNESCO World Heritage Site. Houses 36,000 leather-bound volumes, uniquely protected from pests by a colony of bats. # Why Go 🦇 Witness the fascinating nocturnal bat colony protecting ancient books 📚 Explore a collection of 36,000 leather-bound volumes from the 14th to 19th centuries 🏛️ Admire the grand Rococo design, ornate ceilings, and marble floors 👑 Part of a UNESCO World Heritage Site, showcasing Portugal's golden age # Why Avoid 🚫 Bats are only active at night, so visitors during opening hours are unlikely to see them 📝 Researchers and scholars require a previous appointment for access to the collection # Cost 💰 Entrance to the Palace of Mafra is €6 for adults, children under 12 free. # Hours 🕒 Monday, Wednesday, Thursday, Friday: 9:30 a.m. to 1:30 p.m. and 2 p.m. to 4 p.m.