On March 8, 1978, The Hitchhikers Guide to the Galaxy premiered on BBC radio. The Douglas Adams story was adapted to books, television, and a movie. There are several events to mark the occasion.
I was first introduced to the series though the books. I distinctly remember receiving one with the cover pictured here as a Christmas gift.
While I was searching for a suitable image here, I found old post about the 30th anniversary of HHGTTG. In it, pure gold: A link to the 30th Anniversary re-release of the text game… Have fun!