Gridskipper

While the canal Saint-Martin may be better known for its aboveground scenic possibilities, a significant portion of the canal lies hidden under city streets, from the place de la Bastille to the rue du Faubourg… du Temple. A few river cruise operators — including Canauxrama and Paris Canal — offer daily trips down the length of the canal, along the way providing sightseers with a look at this nearly two kilometer vault running beneath the boulevard Richard Lenoir. Tours run in both directions between the Seine and the Parc de la Villette and cost €15-€17. (photo) [link]

The Denfert-Rochereau Ossuary, known also as the Catacombs, should be on every non-squeamish tourist's list of things to see in the city. Created within a portion of the warren of limestone quarries snaking beneath… the city, the catacombs serve as the final resting spot for the skeletal remains of an estimated five to six million Parisians, relocated there near the end of 18th century, as cemeteries were emptied to free up more land for development. The skillfully arranged bones, grouped by their cemetery of origin, are a truly awe-inspiring sight and a stark reminder of our common mortality. [link]

This archaeological museum located under the large square in front of the Notre Dame cathedral offers a fascinating look at former incarnations of Paris, from remnants of the Gallo-Roman town of Lutetia through… to the medieval city of Paris and the 19th century works of Haussmann. Currently the museum is running an exhibit, "Construire à Lutèce," which details the construction methods used to build Lutetia and runs until May 2008. The museum is usually open Tuesday through Sunday, but will be closed for the month of November. (photo) [link]

Sneak a peek at the smellier side of Paris at this museum devoted to the city's sewer system. Visitors have access to a small portion of the tunnels that transport waste as well as fresh water (separately of course)… throughout the city, and you can view exhibits on the history of the system, including how earlier workers managed to keep these conduits free of debris. Of particular note are the street signs posted in each tunnel, showing which surface street is being tracked below ground, as the hundreds of kilometers of sewer tunnels provide a mirror image of the city grid above. [link]

Before it was a world renowned museum and pilgrimage site for Da Vinci Code fans, the Louvre was the private residence of French royalty. The first building on this site was a medieval fortress, which was… later taken down to make way for the complex of buildings, constantly expanded over the centuries, that house the modern Louvre. Not much trace of the original fortress remains above ground, but visitors to the Louvre can see a good portion of its stately foundations in the Louvre Médiéval exhibit, located on the lower ground floor of the Sully wing. [link]

The Métro system can not only transport you to Paris attractions, but parts of it are just as interesting as anything you can see aboveground. One example of this is the 11 line platform at the Arts et Métiers… station. It's located just below the Musée des Arts et Métiers, a former monastery which now houses a collection of mechanical and scientific artifacts. To mark the 1994 bicentenary of the museum's parent organization, the Conservatoire National des Arts et Métiers, the station was redesigned to look like the inside of a submarine vessel, with copper siding, large mechanical gears and portholes, and it evokes the work of French science fiction writer Jules Verne. (photo) [link]