Ictīnus in Harpers Dictionary of Classical Antiquities
（Ἰκτῖνος). One of the most famous architects of Greece; he flourished in the second half of the fifth century B.C., and was a contemporary of Pericles and Phidias. His most famous works were the Parthenon on the Acropolis at Athens, and the temple of Apollo at Bassae, near Phigalia in Arcadia. Of both these edifices important remains are in existence. Most of the columns of the temple at Bassae are still standing. In the judgment of the ancients, it was the most beautiful temple in the Peloponnesus, after the temple of Athené at Tegea, which was the work of Scopas (Pausan. viii. 41.8). See Parthenon.
Iktinos in Wikipedia
Iktinos (in Latin Ictinus) was an architect active in the mid 5th century BC. Ancient sources identify Iktinos and Kallikrates as co-architects of the Parthenon.
Pausanias identifies Iktinos as architect of the Temple of Apollo at Bassae. That temple was Doric on the exterior, Ionic on the interior, and incorporated a Corinthian column, the earliest known, at the center rear of the cella. Sources also identify Iktinos as architect of the Telesterion at Eleusis, a gigantic hall used in the Eleusinian Mysteries.