That WGVK began public broadcasting in West Michigan! On December 17, 1972 four a day programming began on channel 35. Sesame Street, Mr. Rogers Bob Vila and Broadway all started 40 years ago today.

Here's the story from MLive about the anniversary. The station usually doesn't celebrate anniversaries but they have said the will for this one.

WGVU-TV marks 40th anniversary of its debut as West Michigan's PBS-TV station