The towers of a Japanese castle have been noted for their grace, strength & fagility. They were highly evolved structures and well suited to their roles but ultimately, the relative weakness of the primary material used in their construction - wood, has seen a great number lost over the years.
Tenshu - 天守Of the 100's of central towers ever built, just 12 have stood since the close of the Edo period in 1868. All remain in fine condition. Unfortunately, there was a boom of sorts in the mid to late 1900's of replicas being built of concrete.