Bradlee (Nathaniel J.) is born in Boston.

The son of Samuel and Elizabeth (Davis) Bradlee, Nathaniel Bradlee grows up on Avon Street (then Avon Place), attends the Chauncy Hall School, and like his grandfather and namesake, becomes an architect. He works initially as a draftsman for George Dexter, becomes a partner and then head of the firm. Bradlee lives at 660 Tremont Street, marries Julia Weld in 1856, and moves to Roxbury. A founding member of the Boston society of Architects, Bradlee goes on to design more than 500 buildings between 1856 and 1885. He dies in December 1888 on board a Boston & Fitchburg train while on a business trip to Keene, New Hampshire.