Forza Horizon 5

Very simple achievement.

Go to the Horizon Test Track icon located just out side the main Festival Site. Enter in solo mode and pick any high end S2 car, I chose the Koenigsegg Agera RS, and slap on ALL the upgrades by pressing the button and going through each option.

From here, back out so that you have control of the car. The entire map is considered as the horizon test track so, drive anywhere and everywhere. Best way to get this done quickly is to us the long highway just south of the main Festival stage.

This took me just under 6 passes going up and down the highway. There is also an accolade associated with this called Leaving Tracks and you can pin this to your screen to track your progress. To do this, press to pause the game, select Accolades and then press or twice to go over to the Creative tile and press . Press twice and go over to the Test Track tab. The accolade is located second row from the bottom in the middle column. Hover over the accolade and press the button to pin this to your screen. Any miles you do will be tracked as you do them.

If you have previously completed the accolade, the achievement should unlock when you load into the game.

Additionally, you can use the same car you upgraded to unlock this achievement
Simply take your car to the highway south of the main Horizon festival sight and drive the highway. High end S2 and X class cars can hit 200 very easily and, you won't need to worry about traffic as there will not be any.