This was and will always be the best version of the game. Only if people these days knew. But will never know because you missed the time when it was the game of games. Today's CoD is just... CORPORITE! Back then it was just a few dudes that used the Quake Engine and made something awesome. We used to get free maps and mods and every week was at least 3 or 4 new maps.
Answer: Farm18 side building. Just Recycling Assests.