The reservoir of St. Anargyroi was designed and built during the Napoleonic period. The construction stopped for several years and continued in 1818 under British rule, it was completed in 1821 and in 1861 it was reconstructed, according to a local newspaper. It was the first large community tank of Paxos and the amount of water was enough for the population (of the main village) Gaios.  

This is a standard cylindrical container with a low circular casing and elegant central orifice in which there is an inscription of the year of manufacture. The label is located on the axis of the raised paved runway leading from the gate of the casing towards the orifice.   The gateway of the casing is at the top of a short ladder. Access to the staircase is a road that has been paved with a delicate and charming pattern made from a combination of long logs and stones. The construction details of the tank prove the quality of local craftsmanship and the intentions of the British rule for high-quality projects.  

After the withdrawal of the British from the Ionian islands the structure is characterized by lower construction quality  and less complicated paved surfaces, additions that could be another indication to date that they were made during the 1861 intervention.