The Commodore left the majority of his enormous fortune to his eldest son, William Henry Vanderbilt. William Henry, who outlived his father by just eight years, increased the profitability of his father's holdings, increased the reach of the New York Central Railroad, and doubled the Vanderbilt wealth. He built the first of what would become many grand Vanderbilt mansions on Fifth Avenue, at 640 Fifth Avenue. William Henry appointed his first son, Cornelius Vanderbilt II, as the next "Head of House".