It was 20 years ago Saturday that Sen. Jim Webb (D-Va.), then-secretary of the Navy, stood at the United States Navy Memorial and inaugurated it to the Washington landscape.

This weekend he’ll return to the same spot, to “the Anchor of Penn Quarter,” to ring in the first annual Navy Day, a daylong festivity of maritime history.

“I am honored to join in the celebration this weekend to mark two decades of the Memorial,” Webb wrote in an e-mail, “commemorating the sacrifices made by our United States Navy to keep our country safe and free.”

In partnership with the city and Naval District Washington, which is made up of all the region’s bases, Navy Day is being held “to celebrate the U.S. Navy’s rich contributions to the history, vitality and economy of the District of Columbia and to recognize the continuing partnership with the leaders of our Nation’s Capital,” Navy Memorial Marketing Director Taylor Kiland wrote on the memorial’s MySpace page (and, yes, you can become “friends” on Facebook, too).

Teddy Roosevelt (an actor) will kick off the day at 10 a.m., along with speeches, including one by Webb, and a short traditional Naval ceremony at the memorial, located at Seventh Street and Pennsylvania Avenue Northwest.

Also on hand will be D.C. Councilman Tommy Wells (D), whose Ward 6 encompasses both the Navy Memorial and the Navy Yard along the Anacostia River.

With “lots of fun family activities,” according to Kiland, the kids will have a blast.

There will be performances by the U.S. Navy Band, Ceremonial Guard, the Military Drill Team and the 40-member Capitol Chorus, but for children the highlights will be the exploratory missions on a military Humvee, coastal warfare boat and a mini tall ship on which kids can practice rigging. The Expeditionary Combat Command also will bring a remote robot used to detonate bombs.

So why was Oct. 13 chosen to dedicate the memorial and for this weekend’s event?

“It’s the Navy’s birthday,” retired Rear Adm. Richard Buchanan said. “On Friday, Oct. 13, 1775, the Continental Congress voted to send out boats to defend our shores. … Navy Day focuses on that celebration.”

Or put more simply, “it’s to celebrate the birthday of the finest Navy in the world,” Kiland said.

Traditionally, the anniversary is marked by a 15-minute ceremony and wreath laying, she said, with a little cake and few people.

But this year, to mark the big 2-3-2, that little cake will be enough to feed the more than 500 people Kiland expects to come out to the memorial on Saturday — and the cake will be made by the White House Mess, which is cheffed by active-duty Navy.

More activities are planned just a little down river, where the Navy Yard opens its gates to the public for the first time in nearly eight years (though you can visit some campus sites, like the museum, by appointment throughout the year).

The Navy’s oldest shore establishment, in operation since the early 1800s, is a working base and home to more than 60 tenant commands. Though it has a rich history of building battleships and weaponry, it mainly is now home to various offices including the engineers of the Navy who design and test everything from “engines to guns to radar,” said Philip Molter, Naval District Washington public affairs specialist.

The open house, scheduled from noon to 5 p.m., allows the public to learn about both the history and the future of the sea services.

Looking into the past, there will be tours of the National Museum of the U.S. Navy and the decommissioned destroyer USS Barry. But to see the present, also free to explore will be a 169-foot Cyclone class patrol craft coming up from Norfolk; a SEAL Delivery vehicle, a craft that rides on the back of submarines and gets the Navy SEALs to shore; heavy equipment used by the SEABEEs; and a display by the Naval Criminal Investigative Service including military working dogs.

And be sure not to miss the 9th Annual NJROTC Color Guard Drill Meet at noon, including many area high school students, with the U.S. Navy Ceremonial Guard Drill Team judging and, of course, performing as well.

There will be shuttle service from the Navy Memorial to the Navy Yard via the Eastern Market and Navy Yard Metro stations from noon to 5 p.m.

And for a relaxing end to the day, there’s a special Navy birthday concert by the U.S. Navy Band at 8 p.m. at DAR Constitution Hall featuring “American Idol” finalist Musician 3rd Class Phil Stacey. Free tickets are available at navyband.navy.mil or by calling 202-433-4777.