The remains of the Greek settlement in the locality of Centocamere, and those of the Tempio di Marasà, which have yielded a great variety of relics related to religion, art, and culture, have more recently been added to those of a sanctuary dedicated to Demetra Thesmophoros, stretches of the Greek city walls, and significant monumental evidence from the Roman Imperial age, such as the Museale Casinò Macrì complex.
In the first half of the fifth century BC, the Locrians demolished their archaic temple and rebuilt a new temple in the Ionic style. The temple was designed by Syracusan architects around 470 BC, based on the idea of Hiero I of Syracuse.
The new temple occupies the same place as the previous one but it has a different orientation. The temple was destroyed in the 11th century. The dimensions of the temple were 45.5 by 19.8 metres. The cella is free of supports on the central axes. The pronaos had two columns. The temple has seventeen Ionic columns on the long side, and six on the front. The height of the temple was 12 metres.
The theatre was built in the fourth century BC not far from the ancient city, in the Contrada Pirettina, taking advantage of a hillside slope. The original structure had space for more than 4,500 people; now only the central part of the theatre is visible. Part of the Cavea was cut into the rocks. Each plane was divided in 7 wedges between 6 scales. A horizontal separation divided the upper theater from the lower theatre.
The Château d'Olhain is probably the most famous castle of the Artois region. It is located in the middle of a lake which reflects its picturesque towers and curtain walls. It was also a major stronghold for the Artois in medieval times and testimony to the power of the Olhain family, first mentioned from the 12th century.
The existence of the castle was known early in the 13th century, but the present construction is largely the work of Jean de Nielles, who married Marie d’Olhain at the end of the 15th century.
The marriage of Alix Nielles to Jean de Berghes, Grand Veneur de France (master of hounds) to the King, meant the castle passed to this family, who kept it for more than 450 years. Once confiscated by Charles Quint, it suffered during the wars that ravaged the Artois. Besieged in 1641 by the French, it was partly demolished by the Spaniards in 1654, and finally blown-up and taken by the Dutch in 1710. Restored in 1830, it was abandoned after 1870, and sold by the last Prince of Berghes in 1900. There is also evidence that one of the castles occupants was related to Charles de Batz-Castelmore d'Artagnan, the person Alexandre Dumas based his Three Musketeers charictor d'Artagnan on.
During the World War I and World War II, the castle was requisitioned first by French troops, then Canadian and British soldiers. The current owner has restored the castle to its former glory.