El Escorial has been the burial site for most of the Spanish kings of the last five centuries, Bourbons as well as Habsburgs. The Royal Pantheon contains the tombs of the Holy Roman Emperor, Charles V (who ruled Spain as King Charles I), Philip II, Philip III, Philip IV, Charles II, Louis I, Charles III, Charles IV, Ferdinand VII, Isabella II, Alfonso XII, and Alfonso XIII. VI (1746–1759).
This royal armor, possibly the last made in Europe, is believed to have been presented to the five-year-old Infante Luis (1701–1724), prince of Asturias, by his great-grandfather Louis XIV of France (1638–1715, r. from 1643). Luis was the first Spanish-born Bourbon heir to the throne of Spain and ruled briefly as Luis I in 1724.
Alcázar of Segovia, Segovia, Spain. This castle originally started out as a fort and has served as the royal palace at times in its history. It is designed to look like the bow of a ship emerging from the mountains.
The ancient walled city of Avila sits in the scorched meseta of central Castile, an hour north west of Madrid. It's an ancient redoubt, one of a number encircling Spain's capital. Toledo is possibly my favourite.