Passage 5.14.4
φέρε δή, ἐποιησάμεθα γὰρ βωμοῦ τοῦ μεγίστου μνήμην, ἐπέλθωμεν καὶ τὰ ἐς ἅπαντας ἐν Ὀλυμπίᾳ τοὺς βωμούς· ἐπακολουθήσει δὲ ὁ λόγος μοι τῇ ἐς αὐτοὺς τάξει, καθʼ ἥντινα Ἠλεῖοι θύειν ἐπὶ τῶν βωμῶν νομίζουσι. θύουσι δὲ Ἑστίᾳ μὲν πρώτῃ, δευτέρῳ δὲ τῷ Ὀλυμπίῳ Διὶ ἰόντες ἐπὶ τὸν βωμὸν τὸν ἐντὸς τοῦ ναοῦ, τρίτα δὲ Λαοίτᾳ Διὶ καὶ Ποσειδῶνι Λαοίτᾳ· ἐπὶ ἑνὸς βωμοῦ καὶ αὕτη καθέστηκεν ἡ θυσία.
Come then—since I have already mentioned the altar of Zeus the Greatest—let us proceed to enumerate all the altars at Olympia. My account shall follow the very order in which the Eleans customarily sacrifice upon these altars. First they sacrifice to Hestia, secondly to Olympian Zeus as they approach his altar within the temple, and thirdly to Zeus Laoitas and Poseidon Laoitas; this sacrifice is also offered upon a single altar.