Granville Island is one of my favourite places to go when in Vancouver. Although technically an island, it's located in central Vancouver, on the south shore under the Granville Street Bridge and can be accessed by boat, by car, by bus, by bicycle or on foot.
This is a truly remarkable place if you're up for a bit of market shopping, some fresh seafood, some culture, or just to sit & watch the world go by on the wharf outside the food hall (generally to the tune of a busker or two).