Howarth Park ("how" pronounced like "now") is a beautiful beach that easily rivals the Edmonds Marina. A short woodsy walk leads to a Possession Sound beach, with Olympic and Cascade mountain views, lots of logs for seats and -- unless the tide is in --plenty of room for Frisbee tosses. The off-leash area is at the north end, to the right as you come down the steps from the railroad over-crossing. Poop bags and garbage cans provided. Restrooms and water elsewhere in park. Not wheelchair accessible. The start of the off-leash area is a bit rocky, but there was enough sand along the waterfront for a man and his dog to play fetch in the water.
Downsides: Do not go here if your dog is not under voice control. Right at the beginning of the off-leash area your dog can get onto the train tracks. Bring your own fresh water. Shells and rocks may be rough on dog paws.
Directions: From I-5N heading towards Everett, take exit 192 (Broadway) on the left side of I-5. Very soon after the exit, take the second exit ramp to your right (41st Street/Mukilteo). The ramp takes you to 41st Street -- follow the ramp to the right, to 41st St. After a couple lights, you pass a Safeway on the left and 41st St. becomes Mukilteo Blvd. It goes up a hill.