There are daily buses from Athens to Mystras via Sparti. The bus trip is about 3 hours from Athens to Sparti and 15 min from Sparti to Mystras (change of bus). Buses from Athens to Mystras/Sparti depart from Kifissos KTEL Bus Station. To go to Kifissos KTEL Bus Station, passengers have to take Bus 051 from Omonoia or Bus X93 from the airport of Athens. Buses from Sparti to Mystras are very frequent all day long.
Travel to Mystras by car
To go from Athens to Mystras by car, you follow the National Highway Athens-Tripoli and at the junction of Tripoli, you follow the signs to Sparti. After you pass Sparti, you follow the signs to Mystras. The road from Tripoli to Sparti in not highway but rural and has one line per direction, so extra attention is required. The road trip from Athens to Mystras is about 3 hours.