Svendborg is reachable by highway route 9, which branches of the main highway (E20) across Funen south of Odense, it's about a 25 minute drive. Though the Fynbus' regional bus lines; 121, 162 and 163 mainly uses local roads and take about 1½ hours to do the trip. Trains  are faster and the locals prefered choice, they take 42 minutes from Odense. If you are travelling from Copenhagen, you might want to consider switching to a bus in Nyborg instead, as this might be faster, depending on how long the stop over is.
Svendborg harbour  is open to both leisure sailors and commercial ferry traffic, routes out of Svendborg goes to Ærøskøbing on Ærø and to serveral small islands in the South Funen archipelago.