Historical activity associated with the Teide and Pico Viejo stratovolcanoes occurred in 1798 from the Narices del Teide on the western flank of Pico Viejo. Eruptive material from Pico Viejo, Montaña Teide and Montaña Blanca partially fills the Las Cañadas caldera. The last explosive eruption involving the central volcanic centre was from Montaña Blanca around 2000 years ago. The last eruption within the Las Cañadas caldera occurred in 1798 from the Narices del Teide or Chahorra (Teide's Nostrils) on the western flank of Pico Viejo. The eruption was predominantly strombolian in style and most of the lava was ʻaʻā. This lava is visible beside the Vilaflor-Chio road.