Benjamin Henry Boneval Latrobe (May 1, 1764 – September 3, 1820) was a British-American neoclassical architect who emigrated to the United States. He was one of the first formally trained, professional architects in the new United States, drawing on influences from his travels in Italy, as well as British and French Neoclassical architects such as Claude Nicolas Ledoux. In his thirties, he emigrated to the new United States and designed the United States Capitol, on "Capitol Hill" in Washington, D.C., as well as the Old Baltimore Cathedral or The Baltimore Basilica, (later renamed the Basilica of the National Shrine of the Assumption of the Blessed Virgin Mary). It is the first Cathedral constructed in the United States for any Christian denomination. Latrobe also designed the largest structure in America at the time, the "Merchants' Exchange" in Baltimore. With extensive balconied atriums through the wings and a large central rotunda under a low dome which dominated the city, it was completed in 1820 after five years of work and endured into the early twentieth century.