You're likely thinking of Popocatépetl and Iztaccíhuatl, two famous volcanoes in Mexico.

* Popocatépetl is an active stratovolcano located in the state of Puebla, about 70 kilometers (43 miles) southeast of Mexico City.

* Iztaccíhuatl is an extinct stratovolcano located in the state of México, about 70 kilometers (43 miles) east of Mexico City.

These two volcanoes are close to each other and often appear together in the landscape.