Lead Roof Tiles
For all the reconstructed buildings, the roofs have special roof tiles made of lead. These roof tiles are 1.8 millimeters thick, and made of lead mixed with a little copper. By having copper mixed in, the metal tiles become very hard, durable, and resistant to acid. It is not certain why lead roof tiles were used in those days, but they were actually used for Edo Castle, too. Literature from the Edo period says, "We have used lead roof tiles so that the castle would look magnificent and graceful."