Ancient Thermo is located just outside the village and its history dates back to the Bronze Age. The most important findings from the excavations in Thermo are buildings and arcades of the market of the Aetolians, and the pedestals of statues and other offerings which stood in front of the arches. Two arcades have been discovered (East and West) and they date back to the late 4th or early 3rd century B.C. The eastern portico is 170 meters long. These two arcades are two of the greatest ancient arcades and were located beside an oblong square of about 200 meters long and 21 meters wide. The place looked like a "square street" framed by arcades, a structure that will be used much later in monumental constructions of Roman cities.
Excavations also brought to light the temple of Thermios Apollon, one of the oldest temples of Greece (7th century B.C.). The temple consists of a single nave, which is divided along the longitudinal axis by a colonnade of 12 columns to support the roof. The church is approximately 12 meters wide and 38 meters long. The wooden columns were based on stone bases just like the whole superstructure (entablature) of the building. The entablature was richly lined with clay metopes, triglyphs, gutters and edge tiles. The temple of Thermios Apollon is the first example of Doric style church architecture of ancient Greece. The painted metopes of the temple, artistic remains from the Archaic era, always manage to impress the visitors due to the chromatic variety of the Greek painting tradition.
The site is open to public daily.
In the area you will also find the archaeological museum of Thermo, which houses findings from 2500 years ago. The museum hosts numerous findings of the Mycenaean, Geometric, Classical and Hellenistic periods. Also, there is a special place that houses inscriptions with the Resolutions of the Republic of Aitolian.