RATUK has a website. Please visit ratuk.com
Airspace is full of routes called airways, and navigation points call waypoints. Airspace waypoints are made by 5 letters words which are relatively easy to pronounce. Ratuk is such a word. It is a waypoint over France.
This picture shows F-BVOB, a Piper PA28, flying over french airspace, in the vicinity of RATUK.
Appart from being on ratuk.com, ratuk as a waypoint can be seen here on this chart, just north of Le Touquet.
Ratuk is on an airway leading from northern France into the UK. So flying to the UK or towards the north atlantic would be your best best to overfly RATUK waypoint.
Enjoy the flying.
The RATUK website is simple, yet it follows most recommendations, as can be seen below: