Forêt aux Trois Périls
This forest is located in Gorre (or within or near the kingdom of Logres), and is visited by Lancelot during his quest to rescue Queen Guenevere from Meleagant (Meleagaunce).
The Forest of the Three Perils is named for the three perilous challenges that await those who venture into it. As other Arthurian forests, it is depicted as a mystical and treacherous place, often associated with enchantments and magical beings. The Forest of the Three Perils becomes the backdrop for various adventures undertaken by knights of the Round Table. Knights such as Lancelot, Gawain, and others face these challenges as part of their quests.
The Peril of the Serpent
Knights encounter a serpent or dragon that guards a bridge or pathway. They must defeat the serpent in combat to proceed.
The Peril of the Fiery Serpent
Beyond the first challenge, knights face a fiery serpent that threatens their path. This challenge often involves overcoming the heat and flames to continue their journey.
The Peril of the Two Lions
The final challenge involves confronting two lions that guard a fountain or spring. Knights must overcome these lions to access the water source.
Source
Vulgate Lancelot | 1215-1230