The Tholos at the sanctuary of Athena Pronoia (Ἀθηνᾶ Πρόνοια, "Athena of forethought") is a circular building that was constructed between 380 and 360 BC.
It consisted of 20 Doric columns arranged with an exterior diameter of 14.76 meters, with 10 Corinthian columns in the interior.

The Tholos is located approximately a half a mile (800 m) from the main ruins at Delphi (at 38°28′49″N 22°30′28″E).
Three of the Doric columns have been restored, making it the most popular site at Delphi for tourists to take photographs.

The architect of the "vaulted temple at Delphi" is named by Vitruvius, in De architectura Book VII, as Theodorus Phoceus (not Theodorus of Samos, whom Vitruvius names separately).
The Tholos at the sanctuary of Athena Pronoia (Ἀθηνᾶ Πρόνοια, "Athena of forethought") is a circular building that was constructed between 380 and 360 BC. It consisted of 20 Doric columns arranged with an exterior diameter of 14.76 meters, with 10 Corinthian columns in the interior.
The Tholos is located approximately a half a mile (800 m) from the main ruins at Delphi (at 38°28′49″N 22°30′28″E). Three of the Doric columns have been restored, making it the most popular site at Delphi for tourists to take photographs.
The architect of the "vaulted temple at Delphi" is named by Vitruvius, in De architectura Book VII, as Theodorus Phoceus (not Theodorus of Samos, whom Vitruvius names separately).
Delphi