Which introduces 63 new square kilometres of diverse locations to explore from mountains to rivers to valleys and caves full of glowing crystals. And of course it wouldn't be ARK: Survival Evolved without a new dinosaur - the Deinonychus. Which you can see in the announcment trailer.

Expanded Exploration: Over 63 square kilometres of new land and sea to explore!
Peaks and Valleys: Eight Biomes with a vast array of climates and dangers - tread lightly through the hazards of Skeleton Gorge, see the vistas on top of the Twin Peaks or find remnants of the past at the Lost Temple.
Triple Threat Boss Challenges: A boss arena where players face an epic battle against a Megapithecus, Manticore and Dragon in this heavy-hitting, triple threat encounter! Face familiar dangers in the End-Game Boss encounter in an entirely different way!
New Dinosaur - Deinonychus: Encounter the ill-natured Deinonychus! Similar to the raptor, it uses speed and agility to leap wall ledge to wall ledge as it seeks high vantage points to lie in wait for prey. This contentious beast is fearless and will hunt prey much larger than itself, latching onto a larger dinosaur’s back with its sickle-shaped claws as it starts to feed before its victim is even dead.
Into the Trenches: A large network of caves to spelunk as you delve into unexplored territory featuring different themes and varied perks, including the extensive Aberration Trench.
Secrets from the Ancient Age: Explore scattered ruins throughout the world of forgotten “Valguero” survivors.

The update, which is free for all players, arrives tomorrow on PC with a PlayStation 4 and Xbox One release expected sometime in July.