I'll be spending a weekend in Vancouver with my mom and we're having a hard time finding a hotel. Budget isn't an issue and we want to be within walking distance from restaurants, shops, etc..
The Rosewood Hotel Georgia is not only my favorite hotel in Vancouver, but it's my favorite hotel anywhere. It's in a great location. The service is fabulous. The rooms are beautiful and spacious and the bathroom floors are heated. Plus, they have a Bentley on hand to drop you off or pick you up from nearby spots. It's amazing!
Vancouver's two big hangout are Robson Street and Granville Street with the latter being notorious for late night partying night clubs. If budget is no object then the Fairmont Hotel Vancouver is quite central walking distance to everything. If you're looking to stretch your budget then you can get private rooms at the Vancouver Downtown Hostelling International, else do the dorm beds for the cheapest decent accommodation in downtown. Best way to tour any city including Vancouver is to rent a bicycle.
I second Ross, great spot. The Sutton Place Hotel Vancouver is also nice with a lovely spa and steps away from Robson St. Shopping, where ever you stay make sure to goto the Fairmont Pacific Rim and have a meal in their restaurant- actually all of the food Fairmont Pacific Rim is so yummy.
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Four Seasons is the best overall and great location. Wedgewood is also a very nice more 'boutique' experience also in a great location. L'hermitage also very nice and right in the center.