Starkad

The star Saxo, with its eleven major bodies, 254 light years from Sol, was found during the first Grand Survey but was not profitable for the Polesotechnic League and is outside the Terran Empire although a Terran mission now supports the land-dwelling Tigeries of Saxo V, Starkad, because the Merseians have begun to support the sea-dwelling Siravo. The two native species are natural enemies, like men and wolves on Earth, because the Tigeries' fisheries, seabeast hunts, weed harvests and drag nets disrupt the undersea ecology.

Terrans can breathe on the mountain tops but need helmets at sea level where the oxygen is too dense.

"'Under high atmospheric pressure, there's enough oxygen dissolved in water to support an active metabolism and a good brain. That must be why intelligence evolved in the seas: biological competition like you hardly ever find in the seas of Terra-type planets.'"
- Poul Anderson, Young Flandry (New York, 2010), pp. 47-48.

(Serious scientific speculation in the dialogue of an action-adventure novel.)

The Archer, a merchant ship belonging to the Sisterhood of (the island of) Kursoviki, carries "...timber and spices from Ujanka port down the Chain archipelago." (p. 32) Although a ship has a captain and officers, no town or island has a ruler. Instead, females are organized into associations like the Sisterhood which:

have members not living in any one place;
have their own special languages;
"'...own all important property and make all important decisions...'" (p. 33);
employ males, for examples as crews serving under female officers.

Ujanka, the main Kursovikian port, is on Golden Bay, divided by the Pechaniki River. Sisterhood headquarters is in the West Housing. The homes and trained jungles (including venomous reptiles) of the wealthy are in the High Housing. Dragoika is captain of the Archer, share-holder in a fleet-owning kith-corporation and speaker for the corporation in the Sisterhood but nevertheless "...live[s] in the East Housing, on Shiv Alley itself." (p. 52)

We know nothing of Shiv Alley but the mere addition of the word "itself" is enough to inform us that it is significant, perhaps notorious. Seatraders' Castle guards the port.

The Kursovikians know of, and sometimes drop stones on, Tidehome and Reefcastle, two vaz-Siravo cities at the end of the Chain, but have never suspected the existence of Shellgleam, Vault, Crystal or Outlier, four cities which are on the verge of the Deeps and which complete the Sixpoint of Zletovar. Terrans including Ridenour and Flandry visit the Sixpoint and learn more but that is enough for this post.