Río Abiseo National Park covers a large block of the eastern Andes in the San Martín region of Peru, a tangle of steep cloud forest and high grassland where the mountains fall away toward the Amazon basin. It was set up in 1983 and is a World Heritage site for both its nature and its archaeology. Much of it has never been properly explored, and the interior is reachable only on foot after days of travel, with permits from the authorities.
The wildlife is exceptional because the terrain has protected it. The yellow-tailed woolly monkey, a species that was thought to be nearly extinct, lives here, and so do spectacled bears, mountain tapirs, jaguars and an extraordinary variety of birds and orchids. Mist hangs in the trees most mornings, the forest drips and smells of moss and wet leaf litter, and rivers run white through the gorges. In the park stand the ruins of Gran Pajatén and other stone settlements built into the hillsides, attributed to cultures older than the Incas, with round buildings decorated with carved slate patterns that look like birds and human figures.
For a motorcyclist, the practical choice is to ride the lower edges of the country. The roads of the region climb and drop through remarkably steep terrain, with narrow, winding strips of tarmac and gravel hugging the sides of valleys, and landslides in the rainy season from about November to April are frequent. Mud, fog, rockfalls and trucks on single-lane stretches demand patience, and a day's progress may be short. The dry months from May to September are far kinder, though the mountains still make their own weather.
Larger towns on the approaches have stations and basic services, but they are far apart and quality varies. The park itself is a place to read about and respect rather than to visit casually, and anyone hoping to go in needs proper guidance and arrangements.