Phitsanulok is 380 kilometres north of Bangkok, well-served by all the main forms of transport. The train is the most comfortable option: the Northern Railway from Bangkok's Hua Lamphong station takes around five to six hours to Phitsanulok railway station, which sits right in the city centre. Several express and rapid trains run daily; the overnight sleeper is a practical choice.
Buses from Bangkok's Mo Chit (Northern Bus Terminal) take five to six hours. Phitsanulok also has a small airport (PHS) with daily flights to Bangkok on Nok Air and other budget carriers — the flight takes about an hour and is often surprisingly affordable if booked in advance.
From Chiang Mai the journey is around three hours by bus or train. Phitsanulok sits at a useful junction for exploring the region: Sukhothai is 57 kilometres to the west, making it an easy day trip or a natural staging point for heading further north.