Just to clarify about city-states: City-states refer to cities and the farmland and communities surrounding them. Some city-states are larger than others because their land is more usable and easy to control, but remember that it’s hard to see the borders of the city-state itself just but seeing where the city is.
So Pherae, the setting for Alcestis, is sometimes called an island. Now sometimes they talk about King/Prince Pheres carving Pherae out of Iolcus the city-state. When they say island they could also mean an island from trouble, an area of safety and stability in a region of contested territory. (Remember Jason and Pelias?)
The site we believe to be the remains of ancient Pherae is at modern day Velestino. (Pherae was razed to the ground twice, once because of its own attempts to gain more territory and once because the Syrians have a reputation to maintain.)
Below is an excerpt of a much larger map of Ancient Greece that is worth checking out here.
Line 570 Apollo is referred to as “the Pythian himself.” Pythia is an ancient name for Delphi, the site of the oracle and temple to Apollo. It is where Apollo slew a python god that was guarding “the navel of the world,” where he was “reborn” as a god of prophecy. (Apollo is also referred to as the Delian in other. This refers to his literal birthplace, the island of Delos in the Cyclades.)
Line 580 “From the cleft of Othrys descended a red troop of lions” Othrys is a mountain pretty much directly south of Pherae’s territory.
Line 589-590 “by the sweet waters of Lake Boebias” Lake Boebias is a small lake in south Thessaly, east of Pherae. It is more commonly referred to as Lake Xynias in post Classical texts, although some scholars argue that the two lakes have been conflated, and were actually different bodies of water. Boebias is scheduled to be recreated in Thessaly as Lake Karla. (The location is currently a plain in Thessaly.)
Line 593-594 “where the sun stalls his horses in dark air by the Molossians” The Molossians were a tribe of people who lived in an area referred to as Molossia. (Go figure, right?) Their territory was directly west of Pherae (hence the reference to the sun setting by them) and was bordered by Thesprotia in the north and Acarnania in the south.
Line 596 “harborless Pelian coast on the Aegean main” There’s some confusion about this use of “Pelian” because Pelias was currently the king of Iolcus, and Iolcus has a coast. But it also has a harbor, so my best guess is that the Chorus is referring to Mount Pelion, a peak overlooking the sea east of Pherae.
Lydia, Lycia, Phrygia are all mentioned as far away, inferior places in Alcestis. They are actually all part of Anatolia, or modern day Turkey.
Anatolia was a civilization that was very much not Greek, which is why it’s the go-to reference as a source of slaves and barbarians. In reality, the Hittites and other Anatolian tribes were highly evolved, especially in warfare, and they were a threat to the Greeks, especially those nearest to them, like the Thessalians. Now you know.