Wentworth by the Sea occupies a prominent hilltop position on the island of New Castle, New Hampshire, roughly 3 miles southeast of downtown Portsmouth across the Piscataqua River estuary. The property is reached via a single causeway road, giving it an island-resort character despite its closeness to an urban center. The original grand hotel dates to 1874, built to serve wealthy summer visitors arriving by steamboat from Boston, and its imposing Victorian mass—with wraparound verandas and shingle-clad upper stories—was a fixture of the Gilded Age seacoast hospitality circuit. The property fell into disrepair through the late 20th century before a full restoration completed in 2003 returned it to operation as a Marriott Autograph Collection hotel.
Guest rooms and suites span the restored historic main building and a modern marina tower addition. Harbor-view rooms in the main building face the working harbor and the hotel's private marina, while ocean-view suites on upper floors of the tower command broad Atlantic vistas extending to the Isles of Shoals. Marina suites in the tower wing offer the most contemporary aesthetic and the greatest proximity to the water. All accommodations feature premium bedding and updated bathrooms consistent with Marriott's upscale standards.
The Serenity Spa provides a full menu of body treatments, facials, and massage therapy. An indoor heated pool serves guests year-round, supplemented by a compact but well-equipped fitness center. The resort's private marina accommodates small private vessels and serves as the departure point for sailing charters, kayak rentals, and whale-watching excursions coordinated through the concierge.
Dining centers on Latitudes restaurant, which serves New England seafood and American cuisine with harbor views; the Wentworth Lounge is the primary bar for cocktails and lighter fare. The location 3 miles from Portsmouth's vibrant downtown restaurant district, Market Square, and historic waterfront makes evening excursions practical. The property is a popular wedding and corporate event venue, and its grand ballroom and veranda spaces accommodate large group gatherings throughout the warmer months.
Room types
- Standard rooms
- Harbor view rooms
- Ocean view suites
- Marina suites
Amenities
- Full-service spa
- Indoor pool
- Marina
- Restaurant & lounge
- Fitness center
- Concierge
Location
588 Wentworth Rd, New Castle, NH 03854
43.0648, -70.7123 View on map
Highlights
- Historic Victorian grand hotel dating to 1874, fully restored in 2003 as a Marriott Autograph Collection property
- Private marina with harbor access and arrangements for sailing charters and whale-watching excursions
- Island setting on New Castle with panoramic Atlantic views extending to the Isles of Shoals
- Serenity Spa with full treatment menu and year-round indoor heated pool
- Three miles from Portsmouth's historic downtown waterfront and restaurant district
Tips for visiting
- Request an upper-floor room in the marina tower for the broadest water views; rooms on the historic building's harbor side offer more character but slightly less elevation.
- Portsmouth's Market Square and Strawbery Banke Museum are a short drive or rideshare away—the island location makes walking into town impractical.
- Weekend bookings from May through October can sell out months in advance due to weddings and events; contact the hotel early for peak-season availability.
- Whale-watching boats operate from Rye Harbor, approximately 10 minutes south by car, from late spring through early fall.
- Winter room rates drop significantly while the spa and indoor pool remain fully operational, making the off-season favorable for a spa-focused stay.