I was just realizing that it's been 19 years since the final Hardy Boys Mystery Stories book was published in April 2005 (#190 Motocross Madness, hit store shelves March 2005). It brought to an end a 78 year run for the series that started first appeared on book store shelves in May 1927. If you count the revisions there were 228 stories in the series, plus the Detective Handbook, Ghost Stories, Campfire Stories, SuperSleuths! 1&2 and the 6-book "Be A Detective" series spun-off from the continuity, along with the 1950's Disney Mickey Mouse Club serials, the 1969-1971 cartoon (which influenced the revised 22 and even later Wanderer books) and the 1977-1979 Hardy Boys Nancy Drew Mysteries TV series. Plus there was the aborted Casefiles-like direction that the series was trying to go with books 84 and 85 that was then spun-off into The Hardy Boys Casefiles and it's shared continuity with the Nancy Drew Files and it's spin-offs (such as River Heights that ties that whole continuity into the original Nancy Drew Mysteries continuity).
Yep- that was the end of an era. The Hardy Boys world in the newer book series is quite different now.