One of the highest railway lines in the world (until recently the highest) is the Lima-La Oroya-Cerro de Pasco line, built by Polish engineer Ernest Malinowski.

An excerpt from the article 43 facts about Peru

The higher railway line is in Tibet.

The railway was intended to enable the transport of mineral resources from the mountainous regions of Peru to the port of Lima. Manuel Pardo, Malinowski's friend from the time of his emigration to France and the future president of Peru, became the spokesman for the project. The contract included the construction of a 219 km long railway line from Lima to La Oroya. The first stage was completed in 1893. At the beginning of the 20th century, the line was extended to the center of the mining industry in Cerro de Pasco, and later to Huancayo in the Jauja Valley. All three sections are 332 km long.