While I was growing up along the coast in southern California, summers meant slathering on sunscreen, heading to the beach, and toting the same bag that always seemed to spit out pinches of sand no matter how often it was cleaned. Our beaches are some of America’s favorite summertime oases. So it makes sense that we'd be tempted to bring our canine companions along with us to enjoy the surf at dog-friendly beaches. I apply those same sentiments to myself. Now I live in New York City, and when I got my greyhound Djali, I didn’t want to leave her side, nor she mine. In anticipation of her arrival, I researched where I could take her around the city—which parks, cafes, and shops would be dog-friendly, and how I could exercise her to make sure she both stayed healthy and wouldn’t let her rampant puppy energy destroy my apartment. And as warmer days approached, I also started researching what nearby beaches I could take her to. As a greyhound, her primary instinct and joy is...