Yellowstone National Park, 1988

Published: Sept. 9, 1988, 2:12 p.m.

Too strange to be believed, the natural phenomena that prompted the founding of the US national parks. This archive edition of Letter from America was recorded by one of two listeners, who between them taped and labelled over 650 Letter From America programmes from 1973 to 1989. It was restored by the BBC in 2014.