UPDATE: A travelin' (wo)man

UPDATE: It's been almost two years since I posted all the cities I've traversed their mass public transit systems, so I wanted to provide an update. See my newest cities (in purple) since early 2015 that apply. Not many, but I'm making progress!
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I was thinking this morning that I've traveled a lot in my life and in recent years have found myself wanting to take public or mass transit when visiting other cities and countries, if nothing else, to see how their systems compare to my beloved DC. 

So I cataloged all the US cities and international cities where I've utilized their public or mass transit systems. First note to mention: I say 'mass transit' in addition to 'public' because a lot of time overseas their transit is actually privatized, at least in Europe, and that's a whole 'nother discussion for a different post (andwhyIthinktheUSisbehindontransit, coughcough).

I also would like to define what I consider to be "mass or public transit". This is city/county buses, commuter/regional rail, subways, trolleys and light rails. This does NOT include passenger rail (i.e. Amtrak), planes, ferries, taxicabs, or ride-share services. 

So without any further ado, here is my ever-growing list that I would like to continue to enhance! (ordered by proximity to where I call "home")

Washington, DC (obvi) and surrounding jurisdictions and nearby cities (MoCo, NoVa, etc.)
Baltimore, Maryland
New York, New York
Columbus, Ohio
Nantucket, Massachusetts
Boston, Massachusetts 
Chicago, Illinois
New Orleans, Louisiana 
Las Vegas, Nevada
San Francisco, California 
Seattle, Washington

London, England
Paris, France (twice!)
Pisa, Italy
Rome, Italy
Athens, Greece

Sadly, I've been to plenty more cities and places than this, but either due to circumstance, stupidity or age, we didn't utilize the public transit systems in those places, walked, drove, or cabbed A LOT, or I just don't remember it. Here's to hoping that changes and I can teach my future children about the importance of it someday and cities continue to improve their transit so that tourists feel compelled to use it! 

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Addendum: I also am proud to say that I've now conquered public transit with a baby -- albeit, just the Washington, DC metro, but still, I feel like that's an accomplishment and definitely one to write home about!