^Yep.
Founded in 1964 by an agreement between the Canadian and American governments this international park is situated on the southern end of Campobello Island in New Brunswick. Named in honour of President Franklin Roosevelt (who lived on the island) the island's only permnament road link is with Lubec (Maine), though there is summer ferry service to Deer Island (New Brunswick).
I've heard of this island a few times over the years and what drew me to post the satellite image of it was its unique circumstance, its historical ties to both countries, and its difficulty for this thread's game. The calm water, sandy shore, absense of development, and location of the west side of the island seemed to throw some people way off of thinking this is in the North Atlantic Ocean. As for the hints;
Historical ties to the Depression era
Franklin Roosevelt was president of the United States during the 1930's and '40's. He was a key figure in repairing the economy and strengthening Canada-US relations.
The buildings in the photo date to the 1890's.
The building in the centre of the photo is FDR's summer house and was built in 1897. Two other cottages from that time period are restored and open to the public in the park.
The site is on an island.
Campobello Island, New Brunswick.
One of only four sites like this in Canada.
This is one of only four international parks in Canada. Peach Arch (BC), Waterton - Glacier (Alb), and the International Peace Garden (Manitoba).