On the plain that is crossed by the San Pietro river, an area showing signs of Iron Age settlement, there once stood "Lucus Bormani", the sacred wood dedicated to the water god Borman, which in Roman times became an important resting place along the Via Julia Augusta. Saracen incursions in the later Middle Ages forced the inhabitants to take to the highlands, but from the thirteenth century onwards Diano expanded and became especially important as a commercial centre for the sea trading of olive oil.

After the town was destroyed by an earthquake in 1887, reconstruction work gave Diano an appearance typical of a nineteenth-century Riviera town. The parish church of Sant'Antonio Abate on the Via Aurelia dates from 1862: the marble altars date from the seventeenth century and are situated in the neo-classical interior near to frescoes and paintings from the Genoese school, including the "Death of Saint Joseph" by Luca Cambiaso. The civic museum tells the story of Diano Marino through the centuries and preserves archaeological exhibits from pre-Roman and Roman times (including amphorae and vases from a ship that sank off the coast) and objects from the Napoleonic era and the Risorgimento.

Since Diano was rebuilt, tourism has been the undisputed vocation of a town which offers sandy beaches surrounded by Mediterranean maquis. With its tourist harbour and facilities and the opportunity to practise a variety of sports (from traditional diving to go-karting, bowling and minigolf), Diano Marina is the heart of the Gulf. If you wish, you can take a boat that passes by the most important locations along the Riviera dei Fiori and takes you to do some whale-watching off the coast.

A great event is the is a marvellous display of flowers during the solemn time of Corpus Domini (between May and June): the streets of the town are covered with flowers arranged in special patterns.