You may find it a bit dry from my description, but once there, it's hard to resist the lure of the golden dome.
Built by Louis XIV, the Hôtel des Invalides is the largest architectural project of his reign after Palais de Versailles. It was built for his wounded soldiers, who previously had no option but to live by stealing if they refused to join the abbeys, and they were obligated to take them in.
The construction was undertaken by Libéral Bruant, who built the eastern half of the building on the Grenelle plain between 1671 and 1674. The first group of veterans moved in immediately. Before the western section was completed, Louis replaced Bruant with Jules Hardouin-Mansart, who built the double church of the Invalides. The Soldiers' Church, for the pensioners, opened in 1677. And the Domed Church, reserved for the king and his entourage, opened in 1706.
The Soldiers' Church can be entered through a gallery on the second floor of the main court. It has an austere barrel vault that is 230 feet long, without a transept. There is a custom of hanging captured enemy flags from its ceiling, a custom that dates back to the age of the Empire. The flags hung here all date after March 17, 1814; on this date, the allies entered Paris, and Marshal Serurier, then Governer of the Invalide, ordered the destruction of all trophies.
The Dôme was originally conceived as a mausoleum of the Bourbons at St. Denis, but had never been carried through. The complex, centralized design of the building allowed for optimal light. More than 27,830 pounds of gold (approximately 555,000 gold leaves) was used on the dome, with up to 10 master goldsmiths deployed in 1989 for the production. After December 15, 1840, when Napoleon's ashes were brought back to Paris, the dome became the mausoleum of the Bonapartes. The crypt is 20 feet deep, with an opening 49 feet in diameter; it holds the Emperor's tomb, which is made of Finnish red porphyry.
The central pavilion, with the entrance to the Invalides, is rounded in shape and is decorated with a carved pediment depicting the Sun King.
Pensioners lived in the ancillary buildings with ordinary soldiers, sleeping five or six to a room, whilst officers' rooms had one or two beds. Invalid pensioners had individual rooms in the infirmary. Ten years of military service was the requirement for admittance to the Invalides, and prayers and mass were compulsory. The building can accommodate up to 2,000 veterans, but had 3,000 in 1710, functioning almost as a small town!
After the return of Napoleon's ashes, the mausoleum began to take precedence over the soldiers' homes. Today, cannons no longer fire at the Invalides to announce great events, but it still has a modern surgical hospital and houses the museums of the Army, Relief Maps and Plans, and the Liberation.