The Nordschleife is a historical and well-known race track at Nürburgring.
Porsche took a Le Mans prototype and removed all the limitations imposed to the class: minimum mass, maximum energy storage, and so on.
As a result, they improved the all-categories six minute lap record by one minute.
The video by the on-board camera is there and elsewhere:
https://www.youtube.com/watch?v=PQmSUHhP3ug