Beginning near the intersection of Broadway and Park Row, one of the routes of the railroad extends under Park Row, Center Street, New Elm Street, Elm Street, Lafayette Place, Fourth Avenue (beginning at Astor Place), Park Avenue, 42d Street, and Broadway to 125th Street, where it passes over Broadway by viaduct to 133d Street, thence under Broadway again to and under Eleventh Avenue to Fort George, where it comes to the surface again at Dyckman Street and continues by viaduct over Naegle Avenue, Amsterdam Avenue, and Broadway to Bailey Avenue, at the Kingsbridge station of the New York & Putnam Railroad, crossing the Harlem Ship Canal on a double-deck drawbridge. The length of this route is 13.50 miles, of which about 2 miles are on viaduct. Another route begins at Broadway near 103d Street and extends under 104th Street and the upper part of Central Park to and under Lenox Avenue to 142d Street, thence curving to the east to and under the Harlem River at about 145th Street, thence from the river to and under East 149th Street to a point near Third Avenue, thence by viaduct beginning at Brook Avenue over Westchester Avenue, the Southern Boulevard and the Boston Road to Bronx Park. The length of this route is about 6.97 miles, of which about 3 miles are on viaduct. [Illustration: MAP SHOWING THE LINES OF THE INTERBOROUGH RAPID TRANSIT CO. 1904] At the City Hall there is a loop under the Park. From 142d Street there is a spur north under Lenox Avenue to 148th Street. There is a spur at Westchester and Third Avenues connecting by viaduct the Manhattan Elevated Railway Division of Interborough Rapid Transit Company with the viaduct of the subway at or near St. Ann's Avenue. [Sidenote: _Brooklyn Route_] The route of the Brooklyn Extension connects near Broadway and Park Row with the Manhattan Bronx Route and extends under Broadway, Bowling Green, State Street, Battery Park, Whitehall Street, and South Street to and under the East River to Brooklyn at the foot of Joralemon Street, thence under Joralemon Street, Fulton Street, and Flatbush Avenue to Atlantic Avenue, connecting with the Brooklyn tunnel of the Long Island Railroad at that point. There is a loop under Battery Park beginning at Bridge Street. The length of this route is about 3 miles. The routes in Manhattan and The Bronx may therefore be said to roughly resemble the letter Y with the base at the southern extremity of Manhattan Island, the fork at 103d Street and Broadway, the terminus of the westerly or Fort George branch of the fork just beyond Spuyten Duyvil Creek, the terminus of the easterly or Bronx Park branch at Bronx Park. [Sidenote: _Location of Stations_] The stations beginning at the base of the Y and following the route up to the fork are located at the following points: