Pambamarca (alternate, Pimbamarca) is an eroded stratovolcano in the Central Cordillera of the northern Ecuadorian Andes in Pichincha Province.

Noting that the local indigenous community settled in Pambamarca were docile, the Incas thought that they could move in and occupy the territories outside Quito.

[7] According to a legend that relates to the period, Huayna Capac, ruler of the Incas with an ambitious plan of winning the Cayambe got muddled in a 17 years' war even though they invaded with a large army.

[7] Jorge Juan y Santacilia and Louis Godin, on their voyage through South America to fix signals for surveys, arrived at the "desert of Pambamarca" in early September 1737.

These military structures provided security to Quito fortress and other forts such as Jambimachi, Pambamarca, Pachha, Campana, Olachan Tablarumi, Achupallas, Guachala and Bravo.

On other occasions, he observed arches of white light formed by reflected moonlight, whose explanation is unknown but which may have been related to ice-crystal halos.

The existence of two types of forts and the recovery of many armaments is suggestive of a pre-Columbian borderland, which is an important and rare find in New World archaeology.

[15] The Incan Forts discovered in the Pambamarca extinct volcano region are 20, apart from two fortresses built by the Cayambe, the ethnic people of Ecuador.

According to the Director of the Archaeological Project these are inferred to represent border region between the fortresses built by the Ecuadorian people and the Inca.