242 and 244 West 61st Street
These were the last surviving tenament houses of the dozens that once housed the teeming residents of San Juan Hill. The DOB website does not give their specific ages, although they were listed as Old Law Tenaments, which dates them between the passage of the Tenament House Act of 1879 (the "Old Law") and the "New Law" of 1901.
The rezoning of the block to facilitate the Ginsburg development to the west preserved these buildings, although they were renovated beyond recognition.
Next: 246-250 West 61st