Germany's Nürburgring is one of the most popular racetracks in the world, thanks in part to the track's management regularly hosting “tourist rides” where members of the public can bring their own vehicle and take on the Green Hell.

The current cost of a lap is 35 euros (approximately $39), and the entry also comes with some restrictions. One of these is a minimum speed of 130 kph (approximately 80.7 mph).

According to Road & Track, the minimum speed was only recently increased from a previous speed of about 37 mph, and may mean that some classic cars will no longer be allowed.

There are plenty of other restrictions that apply to vehicles taking part in the tourist rides. Some of them include vehicles needing to be under a specific weight target, and having aerodynamic elements that don't protrude beyond the vehicle's stock dimensions. Vehicles also need to have the driving dynamics of a regular passenger vehicle, thus ruling out pickup trucks and vans.

Naturally, there are also plenty of restrictions when it comes to the actual driving on the 'Ring. Cars need to keep to the right unless overtaking, and no timing of laps is permitted. Any damage caused to the track also needs to be paid for by the driver, as does the need for any towing service should a vehicle break down or suffer a crash.

Whether a vehicle is still covered by regular car insurance is also a tricky issue, as it can vary depending on the country in which the car was insured. To get around this, there are companies set up that provide insurance specifically for the tourist rides.