Yes, that is a geoduck. They grow wild in Washington, mainly in the Puget Sound, but they are raised commercially and harvested, too. They are good, but we have a bunch of other species of clams around here. The best, by far (IMHO) are razor clams. Much more tender if you don't overcook them, and OMG tasty. Also quite good are mussels. I'm sitting about three blocks from Penn Cove, home of the famous Penn Cove mussels. Great eating (although one of the idiot drivers for Penn Cove shellfish was holding up traffic with no passing room this morning, 35 in a 55 zone #*(#$*(#).