Welcome to Portsmouth's iconic South End, where cobblestone sidewalks, waterfront parks, and centuries of history create one of New England's most desirable places to call home. Just moments from Prescott Park, Strawbery Banke, and Market Square, this beautifully updated Colonial offers timeless character paired with thoughtful modern improvements. Dating back to circa 1750, the home showcases classic New England architecture while benefiting from significant 2025 exterior renovations, including a new roof, four skylights, new windows, cedar siding on the front façade, Hardie cement board siding on the sides and rear, and blown-in insulation. Inside, approximately 1,800 square feet provide warm, inviting living spaces filled with natural light, two bedrooms, one bathroom, and the unmistakable charm only a historic Portsmouth home can offer. You'll also love the first floor ADU, complete with an eat-in kitchen, a studio style bedroom, and a full bath comprised of a clawfoot tub and built-in sauna. Perfect for guests or rental income! Outside you'll enjoy morning coffee or evening cocktails on your spacious, private back patio. The oversized shed offers fantastic storage, a work shop, or garage potential. Additional features include natural gas heat (new furnace being installed prior to closing), two 100-amp panels, public water and sewer, a detached storage shed, and 1 off-street parking spot (or more depending on how you use the backyard). Whether you're searching for a full-time residence, a weekend retreat, or a home that perfectly blends historic character with modern improvements, 491 Marcy Street presents a rare opportunity to own in one of the Seacoast's most treasured neighborhoods. Showings start at open house, Saturday July 25th, 12-2pm.