Triceria

Starting at around 130,000,000 A.D. North America, South America, and Australia started to drift towards each other. At around 325,000,000 A.D. the Atlantic Ocean was largely swallowed up. Finally at around 350,000,000 A.D. the three continents merged and formed Triceria. During the 700 million years of existence it became largely uninhabitable, with only its costal regions being habitable. Finally at 1,035,000,000 A.D. the supercontinent broke up due to massive fissures, earthquakes, and volcanic eruptions.