For a large dog with stiffening joints, the best walking surface is flat, even and predictable. Steady movement on level ground maintains muscle and range of motion; uneven footing, steep descents and sudden changes in grade are where an older giant twists, slips or overloads a joint. Virginia Beach happens to offer an unusual quantity of exactly the right kind of ground, and it is free.
That matters more than it sounds because this breed's documented exercise requirement is 2 out of 5. The daily walk is short, so its quality is the whole of it. Twenty steady minutes on a level path several times a day does more for an ageing giant than a single ambitious outing over rough ground.
Sand is the exception worth naming. Loose sand is hard work and unstable footing for a heavy dog, which is fine occasionally and unsuitable as a routine. It is also worth knowing that the city restricts dogs from the resort-area beach during the summer season, so the paved path beside it is the practical year-round option anyway.