I was just out working on the headlights of the Red Car, and I noticed an extra bulb on the bottom of the housing. These have high/low beam bulbs in them, so what is the extra bulb for? Driving lights? Fog lights? Is this something worthwhile wiring to the foglight switch to use? Inquiring minds want to know........

Probably it's is a city light. Meant to be on when your side running lights are on. Small bulb in the bottom of the headlights? I lived in Belgium and you would use your city lights, obviously when your in the city at night instead of your headlights.

Wow, I've never heard of something like that. I guess that comes from my living in the boondocks most of my life. Thanks.

This little bulb?

its wired to my high beam circuit, my car has HID low beam only. That bulb is not used for anything unless I turn on the high beams, then i cant see anything

Nope, it's a separate small bulb at the bottom of the round housing. Separate wiring, too.

Here is an example
Click to view attachment

European housings. Parking lights.

Yup, that's it. Thanks guys.