Plymouth County sits in the heart of Massachusetts cranberry country — the low, boggy terrain inland from the coast is ideal for the crop, and the harvest runs from late September through October. At peak harvest the bogs are flooded, turning the landscape an extraordinary deep red as the berries float to the surface to be corralled by harvesters in waders.
Several local farms offer bog tours during the harvest season. Cranberry World, once a major visitor attraction in Plymouth, has closed, but local farm tours still run in autumn. Check with the Plymouth visitor information for the current season's options. Outside of October, the bogs are visible from roadsides heading south toward Carver and Wareham, but not particularly dramatic.
If you're visiting in autumn, the contrast between the scarlet bogs and the surrounding pine barrens is one of the better pieces of New England scenery that most people don't know about.