At Penn's Landing along the Delaware River, this modern, user-friendly museum celebrates Philadelphia's long seafaring history, covering everything from Philadelphia's 350-year-long shipbuilding industry (which, sadly, ended in the 1980s) to life on board a ship, the waves of immigration that came to Philadelphia directly from the Old Country, and a sensationalistic "Disasters on the Delaware" section, complete with a gazette you can take home detailing the deadly particulars of Revolutionary War naval battles and turn of the 20th century steam-ferry explosions.

You'll learn how Philly native Robert Fulton invented the Nautilus, the first submarine to launch a successful (and survivable) attack on a warship, as well as the unlikely origin of the Slinky in a Delaware River Shipyard in 1944. When you watch the video about the 30,000 workers who flooded into the Hog Island shipyards during World War I, realize that they were in large part Italian immigrants, who carried with them lunches that echoed the foods of their homeland: salami and other cold cuts, cheese, oil, and vinegar, with maybe some lettuce and tomatoes, conveniently stuffed into a long Philly roll. Though the Hog Island shipyard shut down after the Great War, the "Hog Island Sandwich"—originally nicknamed the "Hoggie," though that mutated to "Hoagie" by the 1940s—lives on.

The maritime collection here is first class, but so are the interactive, all-ages exhibits. There's a kindly model shipbuilder on staff to explain his craft, and a working boat-building shop, where you can watch master craftsmen and their students create and restore traditional wooden boats. Just south of the main building are docked the museum's star attractions: the Olympia and the Becuna. This pair of historic sea craft offers a self-guided glimpse of the U.S. Navy of yore.

The larger of the two is the Olympia, Admiral Dewey's 1892 steel flagship from the Spanish-American War. It remains the oldest steel warship still afloat, featuring a restored bridge and handsome, originally furnished examples of an officers' saloon and wardroom, flag officer's cabin, and junior officers' mess. Don't miss the navy's first mechanically cooled water dispensary, a "scuttlebutt," around which sailors would gather to drink and swap gossip.

The Becuna is a 1944-launched submarine, later converted to Guppy Class, that served from World War II all the way into the Cold War. It is a lot longer once you get down in it than it appears from up above, and folding yourself through the hatches separating its compartment and squeezing along its narrow decks will give you a newfound appreciation for tight quarters.