A handful of excellent land reservations around the South Shore  make for great walks—many blessed with spectacular views of the ocean. World’s End (250 Martin’s Ln., Hingham, 781/740-6665, year-round, 8 a.m.–sunset daily, $5 adults, free children), for example, is upwards of 250 acres of rolling hills, wooded paths, and groves—with glimpses of Hingham Harbor and the Boston  skyline throughout. Leashed dogs and mountain biking are permitted.
At the smaller Ellisville Harbor State Park (Route 3A, Plymouth, 508/866-2580, year-round) there are 100 acres of well-tended hiking, fishing, and cross-country ski trails.
Small but charming, the Two Mile Farm (Union St., Marshfield, 781/784-0567, year-round) abuts the winding North River—which it has beautiful views of. The park, which allows pets but no bikes, is considered a local gem for bird-watchers.