The famous love novel was written around 1200/1220. The Tristan material is common across Europe; Gottfried's direct source is likely the version by Thomas of Britain. The novel tells the story of how Tristan meets Isolde and how the adulterous relationship between the two lovers unfolds. Isolde is married to Marke, but she is bound to Tristan by a fateful love potion. The love triangle does not remain hidden, yet Marke is repeatedly convinced of the couple's chastity, notably in the famous grotto scene where Marke finds them innocently asleep. Ultimately, however, Tristan must flee from Cornwall. The novel ends with the tale of Isolde of the White Hand, in which Tristan falls in love in a foreign land. The novel is highly artfully composed and ranks alongside Wolfram's "Parzival" as one of the pinnacle achievements of German literature.