Borgarnes sits on Route 1, the Ring Road, about 75 km north of Reykjavík — a comfortable hour's drive. The Hvalfjörður tunnel (free since 2018) cuts a long fjord detour off the route. Most people stop in Borgarnes on the way to or from the Snæfellsnes peninsula, the Westfjords, or the north of Iceland.
Strætó bus 57 runs between Reykjavík and Akureyri several times a day and stops at the N1 service station in Borgarnes. It is the most useful public transport option, but timetables thin out in winter — check schedules in advance.