German polymath, geographer, naturalist, explorer Alexander von Humboldt died #OTD in 1859.
His most significant and famous expedition was to Latin America (1799 to 1804). Accompanied by Aimé Bonpland, he explored vast regions, including the Orinoco River, the Andes, the Amazon River, and even observed the political & social conditions of the Spanish colonies. His journey also included a visit to the United States.
Alexander von Humboldt at PG:
https://www.gutenberg.org/ebooks/author/1995