The Boyd-Roosevelt Highway
In 1948 Panama issued a set of 5 stamps. Among them is a stamp with a
map of the isthmus with the Canal Zone shaded and indicating the
Carretera Boyd-Roosevelt. The “highway,” properly known as the
Trans-Isthmian Highway, was provided for in the Hull-Alfaro Treaty
signed in 1936. It connected Panama City and Colón and was built by
U.S. troops during World War II. Apart from the Canal and the Highway
no other details appear on the map.