Cairo Montenotte borders the following municipalities: Albisola Superiore, Altare, Carcare, Cengio, Cosseria, Dego, Giusvalla, Gottasecca, Pontinvrea, Saliceto, and Savona.

The urban area reaches an average height of 340 m a.s.l., and it expands in the valley floor along the left shore of Spigno’s Bormida River.

[5] After the Roman Conquest of the Ligurian territory, the Bormida Valley was crossed by the Via Aemilia Scauri, commissioned by the censor Marco Emilio Scauro in 109 BC, that connected the city of Derthona (Tortona) and Vada Sabatia (Vado Ligure), and in Cairo there was the station of Canalicum[6] or Calanico.

[6] The road network was enlarged with the building of Via Julia Augusta, commissioned by Augusto in 13 BC in order to assure the connection with the Gallic provinces.

In the exact place where today stands Nostra Signora delle Grazie Church, there have been found several Roman artefacts and remains of an ancient rustic villa (farm) from the Imperial period.

[8][9][10] The toponym ‘Carium’ made an appearance for the first time in a document from 967 AD,[6] in which the Emperor Ottone I di Sassonia decided to offer to Aleramo several territories already devastated by Lombard and Saracen past incursions.

[6] A bull from Pope Innocent II dated 20 February 1141, cites Cairo's castle, that has been placed under the protection of the Holy See together with the Saint Eugine Benedictine Abbey of Bergeggi Island.

On 5 October 1735 the vast majority of Cairo's territories went under the Kingdom of Sardinia domain,[6] and with the Treaty of Vienna on 30 August 1736 the whole lands were ceded.

With the French domination, on 2 December 1797 Cairo was established as a municipality entering the Letimbro Department, with Savona as a chief town, as part of the Ligurian Republic.

[13] In 1929,[14] Cairo Montenotte underwent the last territorial adjustment when the village of Monti was integrated to it, after the suppression of the municipalities of Santa Giulia and Brovida included in the one of Dego.

In the municipal territory of Cairo Montenotte there are two sites of Community Importance, proposed by the Natura 2000 network of Liguria, for its particular natural and geological interest.

Among the flora is reported the presence of Ligurian saffron (Crocus ligusticus), while among the animal species the black-winged stilt, the red-footed falcon, the hen harrier and the northern lapwing.

[16] The second site, also located between Dego and Rocchetta Cairo, in the Nature Reserve of Adelasia, sees the presence of orchids and quercus × crenata; among the animals the crayfish, the beetle and the greater horseshoe bat.

The economy in Cairo Montenotte is mainly connected to the industries and craftmanship, but the area is also specialized in zootechnical activities that made it gain recognition at a national level, particularly for the breeding of bovine cattle.

Cairo Montenotte's center is crossed by the state highway 29 of the Colle di Cadibona that connects the town to Dego and Altare.

The town is connected to the motorway Autostrada A6 Torino-Savona through the SS29var ‘Variante di Carcare e Collina Vispa’, that originates in San Giuseppe.

The town is also linked to the rail axes Turin-Savona through the San Giuseppe di Cairo train station, located a few kilometers from the city center.