This is a list of named regions on Jupiter's moon Io

Io (moon)

Io ) is the innermost of the four Galilean moons of the planet Jupiter and, with a diameter of , the fourth-largest moon in the Solar System. It was named after the mythological character of Io, a priestess of Hera who became one of the lovers of Zeus....

. These names have been approved for use by the International Astronomical Union

International Astronomical Union

The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

. The features listed below represent a subset of the total known bright regions on Io's surface with many currently not having an officially approved name. These areas are large-scale regions on Io's surface that are notable for their difference in brightness or color from their surroundings. In most cases, these areas are bright terrains, consisting of sulfur dioxide

Sulfur dioxide

Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...

 frost/ice fields, suggesting that they are colder than their surroundings.

The names of regions on Io use a combination of a name derived from locations in Greek mythology

Greek mythology

Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...

 associated with the nymph Io

Io (mythology)

Io was, in Greek mythology, a priestess of Hera in Argos, a nymph who was seduced by Zeus, who changed her into a heifer to escape detection. His wife Hera set ever-watchful Argus Panoptes to guard her, but Hermes was sent to distract the guardian and slay him...

 or Dante's Inferno

Inferno (Dante)

Inferno is the first part of Dante Alighieri's 14th-century epic poem Divine Comedy. It is followed by Purgatorio and Paradiso. It is an allegory telling of the journey of Dante through what is largely the medieval concept of Hell, guided by the Roman poet Virgil. In the poem, Hell is depicted as...

, or from the name of a nearby feature on Io's surface and the descriptor term, regio, Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 for region. Coordinate, diameter, and name source below come from the IAU's Solar System Nomenclature Website.

See also the list of mountains on Io and the list of volcanic features on Io.

Regio	Named after	Coordinates	Size
Bactria Regio	Bactria Bactria Bactria and also appears in the Zend Avesta as Bukhdi. It is the ancient name of a historical region located between south of the Amu Darya and west of the Indus River...	47.6°S 123.77°W	665.68 km
Bosphorus Regio	Bosphorus	1.58°S 120.5°W	1,615.15 km
Bulicame Regio	Bulicame (The Divine Comedy The Divine Comedy The Divine Comedy is an epic poem written by Dante Alighieri between 1308 and his death in 1321. It is widely considered the preeminent work of Italian literature, and is seen as one of the greatest works of world literature... )	34.85°N 190.82°W	498.0 km
Chalybes Regio	Chalybes Chalybes The Chalybes or Chaldoi were a tribe of proto-Georgians. Classical Antiquity credited with the invention of ferrous metallurgy....	57.5°N 86.21°W	760.56 km
Colchis Regio	Colchis Colchis In ancient geography, Colchis or Kolkhis was an ancient Georgian state kingdom and region in Western Georgia, which played an important role in the ethnic and cultural formation of the Georgian nation.The Kingdom of Colchis contributed significantly to the development of medieval Georgian...	1.63°N 205.01°W	2,373.09 km
Illyrikon Regio	Illyria Illyria In classical antiquity, Illyria was a region in the western part of the Balkan Peninsula inhabited by the Illyrians....	69.85°S 169.04°W	750.0 km
Lerna Regio	Lerna Lerna In classical Greece, Lerna was a region of springs and a former lake near the east coast of the Peloponnesus, south of Argos. Its site near the village Mili at the Argolic Gulf is most famous as the lair of the Lernaean Hydra, the chthonic many-headed water snake, a creature of great antiquity...	62.35°S 291.86°W	581.26 km
Media Regio	Media Medes The MedesThe Medes...	8.65°N 59.43°W	2,654.02 km
Mycenae Regio	Mycenae Mycenae Mycenae is an archaeological site in Greece, located about 90 km south-west of Athens, in the north-eastern Peloponnese. Argos is 11 km to the south; Corinth, 48 km to the north...	36.07°S 165.39°W	600.16 km
Tarsus Regio	Tarsus	39.69°S 55.14°W	1,520.93 km