First Lady Pat Nixon attending the reception ceremony

 
From left: Giant Pamdas Ling-Ling and Hsing-Hsing

Two Giant Pandas were given to the United States as gifts by the government of
China following President Richard Nixon‘s visit in 1972. In return, the U.S. sent 
China a pair of musk oxen.The Pandas arrived at the National Zoo in Washington,
D.C.at a ceremony attended by First Lady Pat Nixon. During their time at the Zoo,
the pair had five cubs, but none of them survived past a few days.

Ling-Ling died suddenly from heart failure in December 1992, at which time she was
the longest-lived giant panda in captivity outside China. Hsing-Hsing would go on to
pass her record when he was euthanized by zookeepers in November 1999 at the
age of 28 due to painful kidney failure.