P.J. Clarke's P.J. Clare's signature oysters were developed by Virginia's War Shore oyster company. (Photo courtesy of P.J. Clarke's)

Today is National Oyster Day, which got us thinking about oyster happy hours. The place to start is P.J. Clarke's, which has moved its usual Tuesday oyster happy hour forward one day to take advantage of the "holiday." From 2:45 to 7 p.m., you get 50-cent War Shore oysters, $3.50 DC Brau beers and $8.10 platters of Oysters Rockefeller at the bar and on the outdoor patio.

Other places to enjoy oysters at happy hour:

Black's Bar and Kitchen
Chesapeake oysters are two-for-one from 4 to 7 p.m., and Black's features other discounted seafood, including 50-cent steamed-and-spiced shrimp and $6 plates of fried squid. Beers range from $3.75 (Starr Hill) to $4.25 (Flying Dog), and wines are $5 per glass.

Hank's on the Hill
Both Hank's Oyster Bar and Hank's on the Hill offer $1 oysters from 5 to 7 on weekdays, and half-price raw bar from 10 p.m. to close. But for a package deal, we prefer the Punched, Pounded and Stomped happy hour on the Hill. It includes six oysters and your choice of a can of Narragansett Lager, a glass of prosecco or a cup of the house punch for $10.

Old Ebbitt Grill
From 3 to 6 p.m. and again from 11 p.m. to close, Old Ebbitt offers all of its seafood for half-price. Not only will you get a dozen oysters for $13, you can pick up a dozen littleneck clams for $7, or jumbo shrimp for $1.50 each. The offer even extends to the towering Orca Platter, which has a one-pound lobster, six Jonah crab claws, six clams, a dozen shrimp and two dozen oysters for $60. (Sister restaurant Clyde's offers a similar half-price raw bar deal.)

Pearl Dive
The 14th Street seafood palace offers two-for-one oysters, half-price draft beers and $5 wines by the glass (including cava) from 4 to 7 p.m. Craving mollusks? You'll pay $9 for a full pound of mussels.

What are your favorite oyster happy hours? Let us know in the comments.