Through the Brazilian Wilderness (1914) by

Roosevelt had originally planned to go on a speaking trip of Argentina and Brazil, followed by a cruise of the Amazon River. Instead, the Brazilian Government suggested that Roosevelt accompany famous Brazilian explorer Cândido Rondon on his exploration of the previously unknown River of Doubt, the headwaters of which had only recently been discovered. Roosevelt, seeking adventure and challenge after his recent defeat for a third term in the White House, agreed. Kermit Roosevelt, Theodore's son, had recently become engaged and did not plan on joining the expedition but did on the insistence of his mother, in order to protect his father. The expedition started in Cáceres, a small town on the Paraguay River, with 15 Brazilian porters (camaradas), the two leaders, Roosevelt's son, and American naturalist George Cherrie. They traveled to Tapirapuã, where Rondon had previously discovered the Headwaters of the River of Doubt. From Tapirapuã, the expedition traveled northwest, through dense forests and then later through the plains on top of the Parecis plateau. They reached the River of Doubt on February 27, 1914. At this point, due to a lack of food supplies, the Expedition split up, with part of the Expedition following the Ji-Paraná River to the Madeira River. The remaining party then started down the River of Doubt.