Public bus from Valletta to Mdina
From the bus terminal in Valletta you can take a bus to Mdina. Bus N° 51, 52 and 53 run every 10 minutes and take you to Mdina in about half an hour. A ticket costs € 2.60 per person (valid all day). You can buy it on the bus or at one of the ticket machines at the bus terminal. You can check the timetable in advance.
TIP: Get off at Rabat, the urban district of Mdina. From there it's 500 meters on foot to the historic city center.
How do I get to the bus terminal from the cruise port in Valletta?
The Valletta bus terminal is located just outside the city walls west of the historic city center, about 1 kilometer from the cruise port. You can walk there (20 minutes) or a take a taxi (€ 10, 4 persons, one way).