The Municipal Theater “Apollon” (Apollo), situated within the town center, behind the Municipal Cultural Center and opposite to the cinema “Pallas”, has been designed by the famous Italian architect Pietro Sambo. Constructed in 1862-1864, the theater is ever since, the symbol of the town of Hermoupolis, both during the times of flourishing and in the period of decline.

The general opinion is that the theater is a miniature of the Teatro alla Scala of Milan. However, this view is only partly correct. In fact, the architecture of the building follows more than one model. Apart from the Teatro alla Scala, the theater has adopted architectural features also form the famous Teatro San Carlo of Naples, the theater of Castelfranco and the Teatro della Pergola of Florence, whereas the way the roof is supported follows the French style used in this period of time.

This excellent theater was not constructed in a town indifferent to the theater. On the contrary, Hermoupolis of the years 1830 – 1860 was a town that loved theater and had already a theatrical troupe established by the author Evanthia Kairis, sister of the eminent thinker and author of the Greek Enlightenment Theophilos Kairis. Up to 1864 the cultural and theatrical activities in the city reach their peak. After the construction of the new impressive theater this period of flourishing of theater continues, following the general prosperity and growth of the town. Famous Italian and, later on, Greek troupes present operas and the hit plays of the period. Numerous reports of foreign travelers who had visited Syros in these times praise both the brilliant performances and their success and the elegance of the public attending them.

Despite the decline of Hermoupolis in the following years, theater still keeps flourishing in the period between the two World Wars and its stage always puts on brilliant plays. Unfortunately, during the World War II, the building suffers extended destruction, which led to the need of extensive interventions after the end of the war, which resulted to partly spoil the style of the theater.