Pactya or Paktye (Ancient Greek: Πακτύη) was an ancient Greek city located in ancient Thrace, on the Thracian Chersonesus. It is cited in the Periplus of Pseudo-Scylax, in its recitation of the towns of the Thracian Chersonesus, along with Aegospotami, Cressa, Crithote and then Pactya, situated 36 stadia from Cardia. It is said that Miltiades founded it. Strabo places it on the Propontis between Crithote and Macron Teichos. According to Herodotus, Miltiades the Elder ordered a wall built between Cardia, which was on the coast of Gulf of Melas and Pactya, which was on the Propontis side, to prevent invasion of the Chersonesus by the Apsinthii. Alcibiades retired here the Athenians had for the second time deprived him of the command. It was a member of the Delian League. Pliny the Elder points out that both Cardia and Pactya later joined to form Lysimachia.
- Mogens Herman Hansen & Thomas Heine Nielsen (2004). "Thracian Chersonese". An inventory of archaic and classical poleis. New York: Oxford University Press. pp. 907–908. ISBN 0-19-814099-1.
- Periplus of Pseudo-Scylax 67.
- Diodorus Siculus. Bibliotheca historica (Historical Library). Vol. 22.74.
- Pliny. Naturalis Historia. Vol. 4.18.
- Pseudo Scymnus or Pausanias of Damascus, Circuit of the Earth, § 696
- Strabo. Geographica. Vol. 7, frag. 51, 53, 55. Page numbers refer to those of Isaac Casaubon's edition.
- Herodotus. Histories. Vol. 6.36.
- Nepos, Alc. 7
- Athenian Tribute Lists, §262
- Pliny. Naturalis Historia. Vol. 4.48.
- Richard Talbert, ed. (2000). Barrington Atlas of the Greek and Roman World. Princeton University Press. p. 51, and directory notes accompanying.
- Lund University. Digital Atlas of the Roman Empire.