Cliff faces are among the most extreme environments on Earth. At the heart of Europe, many towering stone walls, elegant rock formations and bottomless chasms have remained astonishingly untouched. No cities were built here, no fields established. For thousands of years, this environment has remained exactly what it has always been: pure wilderness. This vertical world reveals a new face with every passing day. In winter, cliffs become an icy fortress lashed by blizzards, buried under snow and gripped by relentless cold. In summer, these same rock walls become blazing cathedrals of stone shimmering below an unforgiving sun. Spring and autumn are transitional phases that allow plants and animals to adapt to the next period of extremes. Golden eagles circle high above this inhospitable world, while sure-footed Alpine ibex and chamois navigate the rocky surfaces below. However, it is in the cracks and crevices that so much life is found: every day, lizards, spiders, wallcreepers and an astonishing cast of highly adapted creatures battle for territory, food and survival in a vast world of tiny spaces. One creature, above all, has mastered this vertical kingdom: the raven. In “Vertical Worlds”, it is this mythical bird that acts as a guide through an extraordinary world defined by great heights, the terrifying effects of gravity, the freedom and safety of high elevations and specialist lifeforms that have mastered one of the planet’s most hostile habitats.