The Weir Greenhouse across from Green-Wood Cemetery in Brooklyn was built in 1895?and looks remarkably similar 118 years later (if you can ignore the extra decay). Scouting New York paid the place a visit and was inspired to investigate its history. Even though the building was constructed prior to the 1904 World's Fair, many believed the owners had purchased it from the fair and brought it to the spot. The American Institute of Architects once called it a "miniature crystal palace."
Green-Wood Cemetery purchased the building last year and plans a restoration (for which it recently received a $500,000 grant, so it's likely to happen for real). In the meantime, though, parts of the site are much the worse after years of not being maintained.