Speed Camera for Garmin. Does it contains spots on DC's 495 beltway.

Hi everyone,

I got a Garmin Nuvi and updated it with the free trial. I noticed that that it does have have all the speed camera location in the Maryland area. This morning, I was driving on the 495 and saw a flash after I pass an area. In my rear mirror, I saw a SUV with huge flash lights sitting in a hidden area on 495 (somewhere between Montgomery and PG Country line). Does the POI speed camera data contains the mobile speed camera spots even on the 495 beltway?

Thanks,

JC