If you are staying in downtown Portsmouth, check out any of the restaurants, shops, or walk around Prescott Park. Basically everything in Portsmouth is walking distance.
Kittery and York are short drives away.
York has beachs, shops and restaurants.
Jumpin' Jay's Fish Café
150 Congress Street, Portsmouth, NH 03801, (603) 766-3474
Great for Dinner in Portsmouth
The Goat
142 Congress Street, Portsmouth, NH 03801, (603) 590-4628