South Flagler House is Related Ross's twin-tower condominium at 1355 South Flagler Drive on the West Palm Beach waterfront, the first luxury residential high-rise in South Florida by Robert A.M. Stern Architects. The two limestone-clad 28-story towers, named North and South, hold 105 residences of two to five bedrooms, penthouses and guest suites, with interiors by Pembrooke & Ives. Sales launched in November 2023 from $7.9 million to $73 million; the project broke ground in April 2024, secured a $600 million construction loan in June 2025, topped off in November 2025 and is scheduled for delivery in 2027. Related Ross reported more than $500 million of pre-construction sales in the first quarter of 2026 alone. The 3.4-acre site faces the Intracoastal Waterway and Palm Beach island across the water, south of downtown West Palm Beach. The Royal Park Bridge to Worth Avenue is a few minutes north, the Norton Museum of Art and the CityPlace district are a short drive, and Palm Beach International Airport is about 10 minutes west. About 50,000 square feet of private-club amenities include a 25-meter lap pool and a resort pool with cabanas, a spa with hydrotherapy, fitness and Pilates studios, an indoor pickleball court, a golf and sports simulator, three dining concepts with private dining and a wine cellar, a screening room, a library and card room, and children's and teen rooms with a STEM makerspace, all run under Related's Related Life programming.