In the old Google Maps, I would sometimes create a custom map that contained several locations related to a particular topic or trip. In the new Google Maps, I can't see a way to create these maps, or to view my old maps. Is this possible, or has the custom maps feature been removed from Google Maps?
According to The New Google Maps, Now Available (May 17, 2013)
"My Places" is not part of the new Google Maps interface. Click the "options" icon in the black navigation bar, select "My Places" and you'll go back to the old interface. It's a trick that lets you temporarily switch to the old interface. You can also click "classic maps".
However you can still access your "My Places" by going directly to Google Maps - My Places which will contain all of your old maps (which are still editable).
You can also use Google Maps Engine Lite to create and view custom Google Maps.