Pyotr Illyich Tchaikovsky's famed 1812 Overture was first performed, outdoors, at the base of the majestic Cathedral of Christ the Savior in Moscow. His beloved ballet, "The Nutcracker," was introduced to the world at the Imperial Mariinsky Theatre in St. Petersburg. But his Piano Concerto No. 1? Its debut came in — of all places — a concert hall off Tremont Street in Boston, six years before the Boston Symphony Orchestra even existed.