Gracious south-facing Back Bay penthouse in the historic Hotel Agassiz, an 1872 Gothic Revival landmark by Weston and Reed, one of Back Bay’s first “French Flats” buildings. Enter via a marble octagonal lobby with door attendant service to this meticulously restored, sun-filled 4,072 square foot, 3-plus-bedroom, 3.5 bathroom residence. A grand, skylit foyer with white oak floors and fine millwork leads to a formal dining room and family room with marble fireplace, custom built-ins, and Commonwealth Ave Mall views. The chef’s kitchen boasts a 10′ marble island, custom cabinetry, Sub-Zero refrigerator, pantry, and dedicated wine cooler. A sun-splashed sitting room, study with marble fireplace, and guest bedroom suite complete one wing; a primary suite with walk-in closet and marble en-suite bath, plus a second en-suite bedroom, anchor the private quarters. Central AC, ground-floor storage, and bike storage included. Steps to Newbury Street and the Esplanade.