Boundaries between the continents of Earth Boundaries between the continents of Earth The boundaries between the continents of Earth are generally a matter of geographical convention. Several slightly different conventions are in use. The number of continents is most commonly considered seven but may range as low as four when the Americas and Afro-Eurasia are each considered a single continent. According to the definition of a continent in the strict sense, an island cannot be part of any continent, but by convention and in practice most major islands are associated with a continent. There are three overland boundaries subject to definition: While the isthmus between Asia
Middle-earth and despite the additional expense, work and delays involved. The definitive map of Middle-earth was published in "The Lord of the Rings". This iconic map incorporates all the chief locations of the main story, and also includes places from some of the background histories. This map was also published (with various additions and embellishment) as a stand-alone poster: "A Map of Middle-Earth". It is important to note that this map does not cover all of Middle-earth, but only shows the north-west of the continent. This is made more explicit in the revised version published in "Unfinished Tales", which is titled