If you're looking to visit Mycenaean ruins off the main tourist routes, I recommend a day trip to the archaeological site of Mycenae in the Peloponnese. The site features the Mycenaean Acropolis, the tomb of Agamemnon, and the ruins of the Cyclopean walls that protected the city. It's a fascinating historical site dating back to around 1600 BC. Another option for a day trip could be the abandoned/ruined Byzantine city of Mystras which offers intact ruins and breathtaking panoramic views of the surrounding area. Both of these options provide a unique and off-the-beaten-path experience for exploring Mycenaean ruins.