You might want to spend some time browsing the exhibits at Naval Museum, Amadeo Lia Museum, or Museo Diocesano. Some landmarks that you won't want to miss include Lerici Castle, Sarzanello Fortress, and Doria Castle. You can wander around Montemarcello Regional Park, Porto Venere Regional Natural Park, or Parco XXV Aprile if you want a dose of fresh air.