In the pit-scene the extras had to scream and cheer like crazy. At first the crew couldn't get the people to be loud and wild enough. Then the director decided to split them up in two groups. Fans of adverse German soccer teams were put up against each other. It worked. The extras went berserk from then on.
There were about 100 real spiders in this movie. The crew made them harmless by putting wax on their teeth. Each night they were counted. By the end of the movie some of them had escaped. Most died because of the cold, but one spider survived and was later found on the set. The local firefighters decided to keep the spider as a mascot.
For the pit-scene a fake alligator was used, as well as real ones. To calm the alligators down they were put in cold water. For a certain scene, Gérard Depardieu's stuntman was supposed to jump on a model-alligator and surf across the pond. Unfortunately, the stuntman made a mistake and jumped on a real alligator. He just managed to get away fast enough without being hurt by the animal.
In 1999, its budget of $48 million, or 274,620,000 FRF, was said to make it the most expensive French film ever. However, the budget for Asterix & Obelix: Mission Cleopatra (2002) at $47 million, or 327,000,000 FRF, was said to make it the costliest French film ever. Accounting for economic variances, either title may earn this dubious recognition.