Basic shelter is available at Altzomoni Lodge, located by a microwave station roughly halfway between Paso de Cortés and La Joya. There are excellent views of Popo. Each of the three rooms has electricity and four bunk beds. Request the keys at Paso de Cortés before hiking up, and bring bedding, warm clothes and drinking water.
The bed cost is in addition to the national park fee for the same amount. Book in advance, especially for November to March, from the Parque Nacional Iztaccíhuatl-Popocatépetl office in Amecameca.