Hidden high in the Sierra de Guatemala mountain range of northeastern Mexico in the state of Tamaulipas is the northernmost tropical cloud forest of the Western Hemisphere. Within its humid oak-sweetgum woodlands, tropical and temperate species of plants and animals mingle in rare diversity, creating a mecca for birders and other naturalists. Fred and Marie Webster first visited Rancho del Cielo, cloud forest home of Canadian immigrant Frank Harrison, in 1964, drawn by the opportunity to see such exotic birds as tinamous, trogons, motmots, and woodcreepers only 500 miles from their Austin, Texas, home. In this book, they recount their many adventures as researchers and tour leaders from their base at Rancho del Cielo, interweaving their reminiscences with a history of the region and of the struggle by friends from both sides of the border to have some 360,000 acres of the mountain declared an area protected from exploitation—El Cielo Biosphere Reserve. Their firsthand reporting, enlivened with vivid tales of the people, land, and birds of El Cielo, adds an engagingly personal chapter to the story of conservation in Mexico.