|Some say it used to be a Canadian airfield during WWII, and that one corner is named after easy listening music; all we know is, it’s called the TopGear Test Track, and it’s fully rendered and available for play in several configurations, all based upon the Stig’s real-life playground at Dunsfold Aerodrome. What makes this track so special (other than it being featured on a hit BBC car show)? TopGear worked with Lotus to overlay a challenging course onto the old airfield, and each corner is designed to test various aspects of a car’s set-up, like Chicago: a “steady state corner” contrived to test your mettle by drawing out over- or understeer hiding in an unsorted chassis. From Hammerhead down to the famous Gambon left-hander, the track faithfully translates the difficult course into a fully immersive experience perfect for any die-hard TopGear fanatic. Did you remember to keep the throttle pinned through the Bentley sweeper? Fire up the replay to check your technique, watching from the top of the tire stack as you rocket through, just like in the show. Don’t let the track’s fame fool you; it’s technical enough to provide challenges for any player.|
— Official description 
The Top Gear Test Track is a real environment first featured Forza Motorsport 4 and in all proceeding Motorsport series titles since.
Located in Dunsfold Aerodrome, Surrey, United Kingdom, this circuit was made famous by the BBC TV show Top Gear. The track is also known for possessing a unique figure 8 layout featuring an intersection forcing the driver to be aware for other cars on another part of the track.
In late 2016, permission for infrastructure development on the site was granted. This, alongside with Top Gear's gradual demise, suggests its presence in future games is doubtful.
There are four different layouts with reverse counterparts (in exception for the Full Circuit) available, and since Forza Motorsport 6, it has also been playable in 2 different weather scenarios.
- Forza Motorsport 4 featured an additional 1/4, 1/2, 1-mile drag strip and a soccer field. These layouts were omitted from later versions, making them exclusive to Forza Motorsport 4.
- The Aerodrome on which the track is situated on is a former RCAF airbase constructed during WW2.