Berdorf is a sandstone paradise, a micro Red of sorts. Climbers have visited Berdorf since the 1960s, with the first routes being traditional chimney lines and aid routes on pegs. Several chipped pockets date from this early development period. The area consists of roughly 150 routes and variations, many of which are excellent. In the early 2000s, the entire crag was rebolted with solid glue-in bolts. In the same period, climbing at every other crag in Luxembourg was prohibited.
The combination of easy access, good protection, extraordinary rock and nice surroundings make Berdorf a very attractive place in many regards.
On good weather weekends, Berdorf can thus be very overcrowded. In order to protect the amazing place that Berdorf is, it is extremely important to follow some basic rules, such as not going to the toilet right below the routes, packing out the toilet paper, parking only in dedicated spaces, and staying at one of the local campgrounds rather than in a parking lot. The sandstone is fragile after rain, so it's a good idea to let it dry for two days to avoid breaking holds. Please brush the holds after climbing, and try to minimize your impact.
A short and subjective list of the best routes includes Écureuil (aka Kaweechelchen) (5c), Lionel Terray (6a), 5e Anniversaire (6a+), Francolux (6b), Willy (6c), Mike (7a), Arrete, Paulette! (7a+), Infernale (7b), Bobby Brown (7c), Cima Ovest (7c+), Isatis (7c+) and Hermann Buhl (8a+).
There is a dedicated guidebook that you can purchase at Casper's climbing shop: https://www.caspersclimbingshop.com/89-luxembourg
Another useful resource about Berdorf is https://allinyourmindclimbing.tumblr.com
A new guidebook has been published in 2021 with +20 new routes.This guidebook also includes the climbing area "Audun-le-tiche" in France very close to the Lux. border.