It would be difficult to determine exactly what natural phenomena are symbolized by the Hecatonchires. They may represent the gigantic forces of nature which appear in earthquakes and other convulsions, or the multitudinous motion of the sea waves (Mayer, Die Giganten und Titanen, 1887).
Soon after they were born, their father, Uranus, threw them into the depths of Tartarus because he saw them as hideous monsters. In some versions of this myth, Uranus saw how ugly the Hecatonchires were at their birth and pushed them back into Gaia's womb, upsetting Gaia greatly, causing her great pain, and setting into motion the overthrow of Uranus by Cronus. In this version of the myth, they were only later imprisoned in Tartarus by Cronus.
The Hecatonchires remained there, guarded by the dragon Campe, until Zeus rescued them, advised by Gaia that they would serve as good allies against Cronus. During the War of the Titans, the Hecatonchires threw rocks as big as mountains, one hundred at a time, at the Titans, overwhelming them. Hesiod, in continuing the Theogony (624, 639, 714, 734-35) reports the three Hecatonchires became the guards of the gates of Tartarus. Other accounts make Briareus one of the assailants of Olympus, who, after his defeat, was buried under Mount Aetna (Callimachus, Hymn to Delos, 141).
This episode, alluded to in Iliad (i.399ff), is found nowhere else in Greek mythology: at one time the Olympian gods were trying to overthrow Zeus but were stopped when the sea nymph Thetis brought one of the Hecatonchires to his aid, him whom the gods call Briareios but men call Aigaion ("goatish" Iliad i.403). Hesiod reconciles the archaic Hecatonchires with the Olympian pantheon by making of Briareos the son-in-law of Poseidon, he "giving him Kymopoliea his daughter to wed." (Theogony 817).
In a Corinthian myth related in the second century CE to Pausanias (Description of Greece ii. 1.6 and 4.7), Briareus was the arbitrator in a dispute between Poseidon and Helios, between sea and sun: he adjudged the Isthmus of Corinth to belong to Poseidon and the acropolis of Corinth (Acrocorinth) sacred to Helios.
In Virgil's Aeneid (10.566-67), Aeneas is likened in a simile to "Aegaeon," though in Virgil's account Aegaeon fought on the side of the Titans rather than the Olympians; in this Virgil was following the lost Corinthian epic Titanomachy rather than the more familiar account in Hesiod.
Briareus is mentioned in the Divine Comedy as one of the Titans who attacked Jove on Olympus. He is in the pit of the giants in the ninth circle of hell (Inferno XXXI.99). The giant is also mentioned in Cervantes´ Don Quixote, in the famous episode of the windmills.
Cottus plays a role in the Post-Crisis origin of DC Comics' Amazons of Themyscira.
Briareos is the name of one of the combat partners who are the protagonists of the Appleseed manga series and its several film adaptations. Most of the characters in the series are named for entities from Greek mythology; in Briareos' case the significance appears to be fairly superficial, referring to his strength and command of the Hecatonchires cyborg body.
Briareos plays a part in the children's novel The Battle of the Labyrinth, where his name is spelled Briares.
In the 2007 game Ace Combat 6: Fires of Liberation, five enemy super-weapons are named after the Hecatonchires. One was called the P-1112 'Aigaion' Heavy Command Cruiser/Aerial Air craft Carrier, two were called the P-1113 'Kottos' Electronic Warfare Platform and the last two were called the P-1114 'Gyges' Fire Support System.