Dubrovnik's fortified Old Town is pedestrian-only, so once you're in, it's everywhere on foot. It's entered through one of two monumental arched entrances - Pile Gate to the west or Ploče Gate to the east - which are linked by Placa (also known as Stradun), the Old Town's main thoroughfare.
If you arrive in Dubrovnik by ferry or long-distance bus, you'll be dropped at Gruž port, which lies 2.5km north west of the Old Town. Immediately outside the port and bus station, catch local bus 1, 3 or 6 (www.libertasdubrovnik.hr) for Pile Gate. Tickets cost 8 kuna if bought from a newspaper kiosk or 10 kuna when purchased on the bus from the driver. If you decide to walk, it's a pleasant 25-minute stroll. If you are staying in a hotel on Lapad peninsular, which is close to Gruž, you'll follow a similar route to the Old Town – ask at your hotel reception for information about the best bus to take.
Regular daily ferries, run by Jadrolinija (www.jadrolinija.hr), leave Gruž port several times a day for the nearby Elafiti islands of Koločep, Lopud and Šipan.
Note that Dubrovnik is not served by rail.
For general information on public transport on the Dalmatian Coast, see my How to get around Dalmatian Coast page.