From the treaty that settled the Napoleonic wars up to the treaties that ended the First World War, there was a tiny, triangular part of Europe that didn't really fit anywhere, and, in this book, we examine how the neighbouring governments worked out a modus vivendi to cope with this unusual state-of-affairs and, in particular, we review the contingencies for the postal services that were associated with it. For, despite its extremely small size, the triangle of Neutral Moresnet eventually managed to have boundaries, or a point of connection, with no fewer than three European states. The initial differences of opinion about where the boundaries between the Netherlands and Prussia should be initially postponed - supposedly for the short term - but they in fact remained unresolved for almost exactly one-hundred years. During the hiatus, an area of land adjacent to those two countries (or three countries, after Belgium was created) was designated a 'neutral zone' - Europe's first and last, unless we count the road (the route neutre) that, even today, leads from Catalonia to the Spanish exclave of Llivia, inside France. In its day, Neutral Moresnet was a curiosity, occasionally catching the eye of the world's press, such as when it announced that it was going to be the world's first, and only, Esperanto-speaking 'state'. It was no, of course, a state at all, but a condominium of shared responsibility on the part of two governments, like the equally curious Anglo-French condominium of the New Hebrides, which faded into normality as the Republic of Vanuatu, in 1980. Despite its minuscule area, Neutral Moresnet had an impact out of all proportion to its size and managed eventually to be known by as many as eight different names, thereby adding to the confusion and complexity that surrounded its fascinating, and now largely forgotten, place.