The town's name refers to the distance of the main centre from the ancient "Altinum": ad quartum lapidem (a quarter of a mile).
Municipality in the province of Venice, situated on the border with the territory of its provincial main centre, is crossed by the River Sile and overlooks the Venetian Lagoon. It is characterized by the presence of sites of scenic and historical interest, such as the archaeological area of Altino, the Park of the Sile and the Oasis of Trepalade.
The area was inhabited since ancient times and finds attest the presence of settlements since the VI millennium B.C. The first settlers seem to have been the Paleo-Venetian populations, that later submitted the colonization of the Romans, due to the presence of the river that opened into the sea. Lands were reclaimed from the marshlands, roads were built, which helped the area of Altino to develop and become one of the most important commercial centers of the times. After the Fall of the Empire, the territories suffered the Barbarian invasions and was subsequently subjected to the Lombards. The devastation and looting that followed, forced the inhabitants to seek shelter in the safer inland islands of the lagoon and only in the XV century, under the dominion of the Serenissima Republic of Venice, the town returned to be populated.
- the Parish Church of St. Michael the Archangel, whose renovation works began in 1852. It features a red brick façade in Classical style with two pairs of columns and a pediment. Within the single nave are preserved beautiful frescoes and a valuable XVII century painting. The building is flanked by a cylindrical Bell Tower, unique for its shape, with a base covered in white marble. At the top of the tower has been placed a statue depicting St. Michael, an artwork of the artist Romanelli;
- the Church of San Magno the Bishop in Portegrandi, recently built, features a white marble façade of extreme linearity with a tympanum with a mosaic that represents St. Magnus. The interior proposes a single nave plan, embellished with frescoes and decorated altars;
- the XIX century Church of Saints Eliodoro and Sebastiano in Altino;
- the National Archaeological Museum of Altino;
- the Park of the river Sile;
- the Oasis of Trepalade