Driveable APC in e3 2003 build

[Lol_Pop]

I was playing the e3 2003 build and found this strange map called "e3_outpost" you get into a combine APC and plow through a combine base. The APC is fully driveable and you can use the weaponry. This map probably would have been shown off at e3 but I guess they just didn't finish it.

The APC is called prop_vehicle_apc if you were wondering. I find this map to be very intriguing so if you know anything about it please tell me in the comments.

The only thing I found about it was this video that showed an older version of the map