Mycenae is really an interesting place. In fact, for those who have been to Athens, going to the Peloponeese offers lots of potential rewards. One option is to simply rent a car in Pireaus (there are quite a few rental car companies within walking distance of the piers) and drive yourselves. We have found driving in Greece to be quite easy as long as you stay out of Athens. The only caveat is that you need a decent map or (even better) a GPS system.