Well... where to begin. I've got an arms length worth of stuff and rightly so as I grew up there.
Great advice on staying downtown if you're there for a few days. The beaver is a must, but watch the frosty beverages, Vancouver and BC in general are militant when it comes to drinking and driving and have road blocks set up around town to check for them. There's only one road in and out of the Beaver just as an FYI.
Once downtown your options are endless, truly a great city to walk around. From English Bay, to Robson Street, Stanley Park, China Town, Gastown and Yale Town all downtown and walkable though you will be worn out at the end of the day. Great call on the floatplane rides to Vancouver Island, be it Nanaimo or Victoria. From downtown Vancouver you can catch a ride to Victoria harbor, definilty ask about interline or "pilot" rates as they do offer them.
Just outside of downtown you have 4th Ave and Kittsilano Beach (definilty worth while for sight seeing

) Additionally Granville Island is a more than worthy of a visit. Don't let the name fool you as its not truly an Island, instead its full of artisans and a great marketplace full of good eats not to mention the Gransville Island brewery!!!
One absolute must is
La Casa Gelato. 200+ flavors at all times, 500+ in their rotation!!! Ya, some are pretty out there, but definilty worth a visit.
Shoot, all this is making me jealous, definilty time for a visit.
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