Grand early 1900s built 16-room home on one of the largest lots in New Castle historic district with water views! Formerly deemed a private mansion, this sweeping 3,350 sq. ft. 6 BRs/4 bath home with 1950s-built addition features a seldom found unique 4-square footprint and is nestled on prime corner lot with separate carriage home, merely steps from the Delaware River/Battery Park. Whether a historical enthusiast or an informed investor, this property offers endless possibilities. The property can be maintained as a regal single-family residence (multi-generational/au pair) or the generously proportioned home turned into separate condominiums/townhomes, or the property subdivided for new condominiums or new townhomes on attractive lots. This is a once-in-a-lifetime opportunity with incredible potential just waiting to be unlocked! This river-view property is located within walking distance to coffee shops, taverns, restaurants and more with strollable brick tranquil tree-lined sidewalks punctuated with historical homes, less than 6 miles from Wilmington Amtrak train station/downtown Wilmington, 8 mins. from I-95, and merely 30 mins. from Philadelphia Airport. The propertys location alone makes this an incomparable prospect! Homes upgrades include 2 new water heaters/2 renovated baths/carriage home electric (2024), new roof (2020), updated 2nd floor electric, updated kitchen, LL sprinkler system and more. Abundantly rich in character, charm and details, the home was originally built by M. B. Fleming, a wealthy businessperson and property investor. At one period, he and his descendants were the largest property owners in New Castle town proper. Over the years, the house served several residential and commercial purposes and since 1964 the house has been solely the Flannigan residence. Home boasts authentic features of a yesteryear era such as original chestnut pegged 1st floor/original pine 2nd floor, 90% original plaster molding, original inset ceilings, original arched doorways, original 6-inch plus baseboards/decorative chair rail and more. Appreciate a gated manicured English garden, lush vibrant landscaping, sprawling covered front porch and spacious sunlit backyard. Step into home and value classic wide and lengthy hardwood foyer with arches, original elegant parlor with timeless appeal, handsome living room with working FP/build-ins, sun-infused screened-in porch, ornate and guest-worthy dining room, potential 1st-floor primary or designated guest suite and updated neutral-hued kitchen. The sprawling 2nd floor features several roomy secondary BRs with ceiling fans, iconic B & W renovated full hall bath, and primary suite with 2 closets, walk-through dressing room/yoga niche, and renovated luxurious full bath with tucked-away convenient this-level W & D. Additionally corner sunlit office and 2nd floor sitting room/flex space that faces 2nd St. with river views also reside on this floor. 3rd floor is home to private in-law suite or can be separate studio apartment with delightful kitchenette, renovated full bath, walk-in closet, and computer nook. LL has dual-width exterior entrance along with updated electric/replaced windows, functional sprinkler system, French drain, sump pump, and 2nd W & D. The carriage house (only 1 left in New Castle that was built the same time as home with imported brick from England) sits adjacent to main residence. It features electric/replaced wood doors and windows (2024) with an all-brick interior and driveway for 4- plus cars for private, unheard-of off-street parking. This property offers a coveted corner lot positioning with river views, home with everlasting allure, myriad of possibilities and tremendous untapped potential. An almost never available noteworthy home in historic New Castle!