Old Town, Alexandria, VA is very pet-friendly. Most of the retail stores allow pets (I'm not quite sure about the restaurants though) and the stores will have water dishes inside for the doggies. Of course, not all of the store allow pets - some of the antique stores don't, for example. If they don't allow pets, most of the shops have signs posted, but I was very surprised on how many stores and shops allowed dogs.
The specialty of the house are the Los Tios Fajitas. The beef and chicken have been marinated with a special recipe that includes lime juice, pineapple juice and herbs. The fajitas are served with fresh flour tortillas, refried beans, rice, pico de gallo, lettuce, guacamole and sour cream. Fajita choices include chicken, beef, shrimp, vegetables or BBQ ribs. All to be enjoyed at the outdoor seating with your pet.
Every Thursday May thru August, take your pooch on a Canine Cruise with the Potomac Riverboat Company. It's a 40-minute tour of Alexandria's seaport and a great way for you to share some fresh air with your dog. Dogs are free but must be on a 6 ft. flat leash.