"Irem, the Pillared City. She will rise from the zee and the ice like dawn. She will be garlanded with red and decked with gold. The Seven-Serpent will watch you longingly from its high pedestal. You will always arrive as a stranger, but when you leave, some part of you will always remain."
Snake heads? Is that... a hydra? Art from SS.
Irem is an archipelago east of Avid Horizon. It appears to be very close to that dream world Londoners call Parabola. They say it always was, always is, always will be. It is a place where time is confused and collides with itself. The people here talk in riddles, and Irem and Whither are locked in an intense rivalry of rhetoric.
Maybe's Daughter thinks of Irem as her home, as she was conceived in Parabola.
Since time is (for lack of a better term) weird in Irem, it is somehow significant to Salt. It does lie dangerously close to his domain in the distant east, and looking east and speaking poorly of him in Irem will likely incur his curse upon unfortunate zee-captains.
Origin
Irem has many similarities to the ancient lost city of a similar name. Iram of the Pillars, also called Aram, Iram, Irum, Irem, Erum, or the City of the Tent Poles, is a lost city, country, or general area that is mentioned in the Quran. Iram became known to Western literature with the translation of The Book of One Thousand and One Nights.
Quote from the Quran:
[With] Iram – who had lofty pillars/The likes of whom had never been created in the lands/And [with] Thamud, who carved out the rocks in the valley?/And [with] Pharaoh, owner of the stakes?/[All of] whom oppressed within the lands/And increased therein the corruption./So your Lord poured upon them a scourge of punishment.
In other words, the residents of the city (or members of the tribe, as some interpret it) angered Allah and their settlement was driven into the sands, never to be seen again. The city is often associated with Ubar, the "Atlantis of the Sands." This could mean Irem fell to the Neath around when the Second City fell, although it could be as old as the First.