I have an American passport and a German one.
Not counting airplane stopovers I've been to:
USA (only including ones that most people have heard of):
Minneapolis/St. Paul, Minnesota
Portland, Oregon
Omaha, Nebraska
San Diego, California
Los Angeles, California
Seattle, Washington
Chicago, Illinois
Phoenix, Arizona
Salt Lake City, Utah
All I can think of for now.
Canada:
Vancouver
In Europe:
Germany:
Karlsruhe many times.
Frankfurt
Munich
Baden-Baden
Austria:
Salzburg
And hiking in the Montafon region.
France:
Paris
Italy:
Florence
Venice
Rome
Pisa
Greece:
Athens
Santorini
I'm going to go to Wales this Summer probably.
===============
Mexico:
Puerto Vallarta
Los Cabos
Cancun
Cozumel
I think that's it.