How do I teach Chrome's omnibar to search in Google Maps?

You'll have to add a custom search engine. Click on Chrome Menu → Options → Basics → Manage Search Engines. Under Add other search engine, add the following:

• Name: Google Maps
• keyword: maps.google.com
• URL: https://www.google.com/maps/search/%s

Now, type maps (and hit tab) followed by the keyword will search for the keyword in Google Maps.

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