Santa Teresa di Gallura is located on the northern-most tip of Sardinia and in sight of the Corsican coast, so getting there by ferry is a unique way to arrive. It’s only about 50 minutes from Bonifacio, Corsica, which also makes the Corsican port a great day trip from Santa Teresa di Gallura.
For getting to and from Santa Teresa di Gallura from the Italian peninsula, your best bet is to take a ferry into Olbia, located just south of Santa Teresa di Gallura. Ferries arrive here from Civitavecchia (near Rome), Livorno (Tuscany) and Genoa (Italian Riviera/Liguria). Then from Olbia you can catch a shuttle bus to Santa Teresa di Gallura.