521 Park Avenue, 1930.

The apartment building at no. 521 was constructed in 1911, and designed by architect William Boring, who is best known for the Immigration Station on Ellis Island. In 1913 the 12-story building was awarded an honorable mention by the New York Chapter of the American Institute of Architects. Its decorative metal balconies (some which run the width of the building, and others considerably shorter) have been preserved.