The Westinghouse Time Capsules were created for 1939 & 1964 World's Fairs. Both are buried 50 feet below New York's Flushing Meadows Park, the site of both world's fairs, the 1965 capsule 10 feet north of the 1938 one.

Both are to be opened at the same time in 6939 AD, five thousand years after the first capsule was sealed. Check out the messages from Einstein et al.