I just drove by this location and saw two cars parked there. They looked a little lonely and there's really nothing in the immediate vicinity, so if someone was breaking into your car they wouldn't run into trouble. On the other hand, I'm going to try it because my car is nothing special.

Also, to clarify, the spots are on Elk Ridge inbetween the BWI Business rail station and the McDonalds. There are some no parking signs on the side of the street, but there are several large gaps that are not addressed by any signs. In other words, I doubt you'd get towed but if you did you could take pictures.

Also, a clarification: If you're driving to BWI from I-95 on I-195, do NOT take the Elkridge exit! This may seem obvious as it is still a ways from the airport, but I thought this was the exit (and thought perhaps it was a local road to BWI). It is not. To find Elk Ridge, follow the signs to long term, off-site parking.

Is the road that goes to Park N Fly a private road? It doesn't look like it is...if Park N Fly owned it, wouldn't they have just connected their lots? There was plenty of street parking between the two lots, where they also park their vans. :-)