Original: The volcano is part of the Ruiz Tolima volcanic massif (or Cordillera Central), a group of five ice-capped volcanoes which includes the Tolima, Santa Isabel, Quindio and Machin volcanoes.
Simplified: The volcano is part of the Ruiz-Tolima volcanic massif (or Cordillera Central), a group of five different icy stratovolcanoes.