The city has a long history and a glorious past. Its greatest prosperity coincides with the years of the Roman Empire. The urban fabric of the modern city is scattered with important findings of the Roman period such as the renovated Roman theater, which still hosts performances, the Hippodrome, the Aqueduct, the bridge of Melichos, scattered Nymphaea and foundations of dwellings, as well as the largest collection of houses of the country housed in the modern Archaeological Museum of the city.

The Apostle Andreas martyred in the city and his remains were buried there. In the middle of the 4th century, with the actions of the emperor Constantine, the Holy Relic was transferred to the Church of the Holy Apostles in Constantinople. When the Franks conquered the city, the Relic was transported to Italy. It was on September 26, 1964, when the Holy Cross of the Apostle was returned to Patras by Pope Paul and after actions of the people of Patras and the Orthodox Church.

The old church of Agios Andreas was built between the years 1836-1843 on the site of a sanctuary of Demeter. At the same point in 66 AD. The first disciple of Christ and patron saint of the city died on the cross. The jewel of Patras, the newest church of Agios Andreas, was founded in 1908. It has a capacity of 7,000 people and is the church of the patron saint of the city. It is the largest church in Greece and one of the largest in the Balkans. Inside is kept the chariot of the Saint and part of the Cross on which he testified.

From the Byzantine period the city is crowned by its castle with important fortifications by the Venetians and the Turks. A castle connected to the local legend of Patrinela. The Turks also built the two opposite castles at the entrance to the Corinthian Gulf, the castles of Rio and Antirio.

In 1821 Patras was one of the first cities in the Peloponnese to revolt against the Turks. After the liberation, the modern city was built by Kapodistrias on the site of the ancient, with the Hippodameian architectural care of Voulgaris. Its neoclassical character survives even today in the midst of modern apartment buildings. A prime example of the city's neoclassical architecture is the Apollo Theater, a work by Ziller, located in the central George I Square.

The modern Rio-Antirio bridge connects the suburb of Patras Rio with Antirrio, connecting the Peloponnese with western Central Greece. In addition, the city boasts of its largest European, Mediterranean-type carnival, the famous Patras Carnival, the main features of which are the satirical and spectacular chariots and spectacular dances and parades.