A famous location from the Hot Version videos is the Gunsai Touge. It is the place where cars from tuners from Japan battle to be the fastest. The location is actually a cycle sports center which is occasionally hosting time attack events for cars. The facility was founded in 1983 for nurturing professional cyclists. In 2002 the facility was taken over by a private organisation.
The length of the full circuit is 5890 meter with very tight lanes and a lot of height differences.
Car related events occasionally held but it is also possible to rent the course. In the center area of the facility are also a small attraction park and a restaurant.
A big city that is close by is Numata. It is advised to go by car.
A link to website for time attack:
http://www.tohge.com/01guide/index.htm
Link to the cycle sports center facility website:
Gunma Cycle Sport Center website
And link of the location on Google Maps: