This pen-and-ink watercolor map shows the Iténez-Guaporé River Basin. The map shows the location of the fortress of Nossa Senhora da Conceição dos Portugueses and the deployment of Spanish troops under command of Alonso Berdugo and Aymerich Tete. This river, now known in Brazil as the Guaporé, forms the border between the Brazilian provinces of Rondônia and Mato Grosso, before flowing north into Bolivia, where it is known as the Iténez.