Naturalist trips awaken my instinct for nature and enrich my vision as an ecologist. They are an opportunity to observe and try to understand the relationship between man and nature. From Yellowstone National Park to Switzerland, from the forests of Belarus to those of the Balkans, and from the African wilderness to that of Costa Rica, all the examples presented in this book show the beauty of wilderness, underline the irreplaceable richness of freely evolving environments, and remind us of the difficulty of humans to live in nature without destroying it. These travelogues are the occasion of formidable lessons of ecology and lead to show humility in front of nature. This book is intended for naturalists, conservation professionals and beyond to all those who love nature and travel.