This star has an Earthlike rocky planet inhabited by yet another repeat of the Cenozoic Earth biosphere, and a gas giant with a moon inhabited by creatures that for the most part could not survive on Earth. They've made contact recently, and they understand each other well enough to collaborate on mathematical research and discuss who gets first dibs on the various asteroids, but that's about all.
So there exist, in most of the human polities, people with experience in xenodiplomacy, templates for treaties with newly contacted aliens, and various not-totally-worthless bits of first contact infrastructure.
The Earthlike planet has two continents separated by a narrow sea, and on the shore of that sea there is an ancient country known these days as Linver whose supreme court still honors its compact with Lyrial Imperator signed some two thousand years ago. The compact, which has been published in thirteen languages, requires that Linver eternally enforce a code of laws that may have been downright humane when it was invented - an unchanging flat tax that people could learn once so illiterates would never need to take a tax collector's word for how much they owed, a ban on nonconsensual marriage (anyone marrying without the consent of both the bride and her father is to be executed; another relative more closely related to the bride than to the groom is acceptable if the father is dead but the bride's consent in particular is always required), a ban on clandestine marriage, a ban on hereditary slavery, a ban on torture (defined both as a violation of bodily integrity to achieve the end of extreme pain, and also as anything on a very long list of formerly-common examples), a ban on the genital alterations formerly commonly done to children, bans on usury and gambling, and enough other things to fill several pages. Several of the things on the list get the death penalty. About fifty thousand people in Linver are currently wanted on capital charges (the list is published regularly); about thirty were executed last year.
People elsewhere describe Linver in various ways, such as "actually run by organized crime" and "surprisingly okay for being arguably a failed state". A guide for tourists and business travelers, published about ten years ago in a country five hundred miles away, is largely taken up by information about the lovely local scenery and local restaurants and the peculiarities of the local dialect and local street signage, but has a wealth of other useful tips, including: travelers are allowed not to wear face masks in Linver if they don't feel like it; travelers should sneak in through one of these suggested routes and avoid coming to the government's notice, but immediately visit a clandestine gambling den to place a bet against being found to have assaulted or robbed anyone during their stay; the whole area from the abandoned Southshore docks to Blueberry Hill is deeply unsafe and best avoided; the bras d'honneur is the local rude gesture and the OK sign is a non-rude way of saying no so it's best not to get offended by it; you can buy insurance against being the victim of theft or battery or fraud, sort of like insurance for natural disasters but for unnatural disasters, and you probably should because the police won't help you; and information about how prediction markets work in general.
There aren't exactly signs pointing out where to go, but perhaps with the ability to read anything ever published and examine models of cities for secret basement lairs it could be done.