While some of the swankier Kennebunkport properties like the White Barn Inn and Cape Arundel don’t allow children, the Seaside Inn is known for its family friendliness: Guests under 12 stay free, complimentary cribs can be reserved in advance, and the double bedrooms—at approximately 405 square feet each—are particularly roomy. It’s also the only inn to be situated directly on Kennebunk Beach, making beach jaunts (with tots and toys in tow) ridiculously easy. In fact, family represents a crucial part of the inn’s core: The Seaside Inn is one of the oldest continually family-run businesses in the country, currently operated by ninth-generation owners Trish and Ken Mason. But its biggest claim to fame is as America’s oldest inn, with documents dating it back to 1660. Besides the oceanfront hot tub, amenities at the main inn stick to the essentials, but guests particularly enjoy the homespun complimentary breakfast of house-baked muffins and steel-cut oats, served in a 150-year-old wood-paneled room. The Masons also rent out four decidedly more luxe beach houses, located directly behind the main inn. Each has either an ocean or a river view and a shell path that leads to the beach.