Physical geography The scenery is Peru is stunning and more varied than I saw anywhere else in South America. The Andes mountains run down through the middle of Peru and form a region called the Sierra. Here it got really hot during the day, but it was freezing at night. The highest mountain is Mount Huascaran which is 6,768m tall. After looking at this I went south to Lake Titicaca which is on the border with Bolivia. It's absolutely huge (8,288 square km) and is the highest navigable lake in the world (3,750m high). I also saw both glaciers and hot springs. To the sides of the Andes is a stretch of rolling hills and flat plains called the Montana. I travelled across this on my way to the Pacific Ocean. On my way I passed through rainforest and over the Amazon river. The Costa is in the far west of Peru, and like the name suggests, it's on the coast. Here I saw sea lions, pelicans, flamingo and a strange bird called the brown booby. Close to the coast is the Sechura Desert. It's one of the driest places on earth and it hardly ever rains here. The climate in Peru is all a bit confusing as the dry season in one area happens at the same time as the wet season in another. I was there in February when it was dry and clear on the coast, but wet and muddy in the mountains and the rain forest. June, July and August would have been dry in the mountains, but the beaches would have been covered in fog. It probably won't surprise you to hear that it rains most days in the rainforest, but most of the time it only lasts a few hours.