According to Hesiod, there were three thousand (i.e. innumerable) river gods.Hard, p. 40; Hesiod, Theogony 364–368, which says there are "as many" rivers as the "three thousand neat-ankled daughters of Ocean", and at 330–345, names 25 of these river gods: Nilus, Alpheus, Eridanos, Strymon, Maiandros, Istros, Phasis, Rhesus, Achelous, Nessos, Rhodius, Haliacmon, Heptaporus, Granicus, Aesepus, Simoeis, Peneus, Hermus, Caicus, Sangarius, Ladon, Parthenius, Evenus, Aldeskos, and Scamander. Compare with Acusilaus fr. 1 Fowler [= FGrHist 2 1 = Vorsokr. 9 B 21 = Macrobius, Saturnalia 5.18.9–10], which says that from Oceanus and Tethys, "spring three thousand rivers". These included Achelous, the god of the Achelous River, the largest river in Greece, who gave his daughter in marriage to AlcmaeonApollodorus, 3.7.5. and was defeated by Heracles in a wrestling contest for the right to marry Deianira;Apollodorus, 1.8.1, 2.7.5. Alpheus, who fell in love with the nymph Arethusa and pursued her to Syracuse, where she was transformed into a spring by Artemis;Smith, s.v. "Alpheius". and Scamander who fought on the side of the Trojans during the Trojan War and, offended when Achilles polluted his waters with a large number of Trojan corpses, overflowed his banks nearly drowning Achilles.Homer, Iliad 20.74, 21.211 ff..
According to Hesiod there were three thousand (ie innumerable) river godsHard p 40; Hesiod Theogony 364–368 which says there are "as many" rivers as the "three thousand neat-ankled daughters of Ocean" and at 330–345 names 25 of these river gods Nilus Alpheus Eridanos Strymon Maiandros Istros Phasis Rhesus Achelous Nessos Rhodius Haliacmon Heptaporus Granicus Aesepus Simoeis Peneus Hermus Caicus Sangarius Ladon Parthenius Evenus Aldeskos and Scamander Compare with Acusilaus fr 1 Fowler [= FGrHist 2 1 = Vorsokr 9 B 21 = Macrobius Saturnalia 5189–10] which says that from Oceanus and Tethys "spring three thousand rivers" These included Achelous the god of the Achelous River the largest river in Greece who gave his daughter in marriage to AlcmaeonApollodorus 375 and was defeated by Heracles in a wrestling contest for the right to marry Deianira;Apollodorus 181 275 Alpheus who fell in love with the nymph Arethusa and pursued her to Syracuse where she was transformed into a spring by Artemis;Smith sv "Alpheius" and Scamander who fought on the side of the Trojans during the Trojan War and offended when Achilles polluted his waters with a large number of Trojan corpses overflowed his banks nearly drowning AchillesHomer Iliad 2074 21211 ff