It is a municipality in the province of Alexandria, situated in the Monferrato area, at the intersection of three main roads, surrounded by green hills and crossed by the river Bormida. The city center is divided into three districts (Borgo Nuovo, Borgo San Pietro and Borgo Pisterna), which together form the oldest part that over the centuries has spread into surrounding areas, up to the area on the other side of the river, where recently two new districts have been built featuring Spa/wellness hotels.
Although artifacts dating from the Paleolithic Ages have been found in the area, the only certain traces of the presence of human settlements are of the Neolithic period. During the Bronze Age the Ligurians settled here, but were invaded and defeated by the Romans led by consul Marcus Pompilius Lenate in 173 B.C. Later in 109 B.C. the Romans built the via Emilia Scauri, named after Iulia Augusta. The road was a vital link between Gallia and Spain and this gave strategic importance to Acqui, thanks its three thermal plants, already described by Pliny the Elder, of which today some traces remain. Entitled municipality, it ruled over a vast territory and was equipped with an impressive and functional aqueduct. After the fall of the Empire it became a Bishopric and towards the end of the VI century it was conquered by the Lombards. During the reign of Otto II, the public power was exercised by the Bishop: Acqui clashed several times with the city of Alexandria with the intent to free itself from the control of Bishop. In the XIII century Acqui was subjected to the dominion of Marquis William VII of Montferrat, then to a branch of the Palaeologi Family, except for the brief period of domination of Anjou. In the XV century it was occupied by the Visconti and in the XVI century it passed to the Dukes of Mantua and was annexed to Savoy Piedmont in 1708.

Not to miss:
- the Church of San Francesco, which preserves inside two XV century cloisters of an ancient Franciscan monastery once connected to it, the apse and the Gothic bell tower represent the remains of the old structure, which was rebuilt in the XIX century in Neoclassical style and embellished by a fine wooden door, artwork of Giulio Monteverde. The façade, surmounted by a pediment is decorated with columns, frescoes by Pietro Ivaldi Ponzone and a canvas that features a hunting scene by Moncalvo.
- the Cathedral of Santa Maria Assunta, built in the X century, features a Latin cross plan in Romanesque style, with five apses and five aisles, a large Roman crypt, a portal of Pilacorte, a Baroque style rose window of the late XV century, a XVII century porch and a Gothic Bell tower is of 1479. The decorations inside date from the XVIII and XIX centuries, feature an altar and a triptych of the Annunciation of Bermejo dating from the XV century.
- the early Christian Church of St. Peter, which has been repeatedly rebuilt and remodeled, almost completely. Rebuilt in Romanesque style between the X and the XI centuries, today it presents an XVIII century neo-Romanesque style, modified again in 1930
- the "Bollente", a marble shrine dating back to 1879, designed by Cerutti and located in the square, from which, springs water, rich of sulphurous-salty-bromine-iodine at a temperature of 74 degrees.
- the Town Hall, dating from the XVII century, was the residence of Lupi di Moirano, now seat of the Town Hall.
- the Bishop's Palace built between the XV century and XVI centuries.
- the ancient hospital of Santa Maria Maggiore of the XV century.
- Casa Robellini, built in the XVI century and refurbished in the XVIII century. Today it houses the Enoteca Regionale.
- the Paleologi Castle built in the XV century by William VII Paleologo, Marquis of Monferrato, and houses the Municipal Archaeological Museum
- the Civic Tower, which was built in 1763.
- the remains of an aqueduct of the Roman Imperial era, which originally was 13 kilometers long.
- the Spas, one rebuilt in 1687 on the ruins of the previous building destroyed by a landslide and a second one built in the early XIX century.