In 1797 was built, where the burying-ground had been, an arsenal which extended from Twenty-fourth Street and over the site of the Worth Monument.

In the City Plan, completed in 1811, provision was made for a parade-ground to extend from Twenty-third to Thirty-fourth Streets, and Seventh to Third Avenue. The Commissioners decided that such a space was needed for military exercises, and where, in case of necessity, there could be assembled a force to defend the city. In 1814, the limits of the parade-ground were reduced to the space between Twenty-third and Thirty-first Streets, Sixth and Fourth Avenues, and given the name of Madison Square.

House of Refuge

The Arsenal in Madison Square was turned into a House of Refuge in 1824, and opened January 1, 1825. This was the result of the work of an association of citizens who formed a society to improve the condition of juvenile delinquents. The House of Refuge was burned in 1839, and another institution built at the foot of Twenty-third Street the same year. A portion of the old outer wall of this last structure is still to be seen on the north side of Twenty-third Street, between First Avenue and Avenue A.

In 1845, at the suggestion of Mayor James Harper, Madison Square was reduced to its present limits and laid out as a public park. Up to this time a stream of water had crossed the square, fed by springs in the district about Sixth Avenue, between Twenty-first and Twenty-seventh Streets. It spread out into a pond in Madison Square, and emptied into the East River at Seventeenth Street. It was suggested that a street be created over its bed from Madison Avenue to the river. This was not carried out, and the stream was simply buried.

Post Road

The road which branched out of the Bloomingdale Road at Twenty-third Street, sometimes called the Boston Post Road, sometimes the Post Road, sometimes the Boston Turnpike, ran across the present Madison Square, striking Fourth Avenue at Twenty-ninth Street; went through Kipsborough which hugged the river between Thirty-third and Thirty-seventh Streets, swept past Turtle Bay at Forty-seventh Street and the East River, crossed Second Avenue at Fifty-second Street, recrossed at Sixty-third Street, reached the Third Avenue line at Sixty-fifth Street, and at Seventy-seventh Street crossed a small stream over the Kissing Bridge. Then proceeded irregularly on this line to One Hundred and Thirtieth Street, where it struck the bridge over the Harlem River at Third Avenue. The road was closed in 1839.

The monument to Major-General William J. Worth, standing to the west of Madison Square, was dedicated November 25, 1857. General Worth was the main support of General Scott in the campaign of Mexico. His body was first interred in Greenwood Cemetery. On November 23rd the remains were taken to City Hall, where they lay in state for two days, then were taken, under military escort, and deposited beside the monument.