Traditionally, Anatolia is considered to extend in the east to an indefinite line running from the [[Gulf of Alexandretta]] to the [[Black Sea]],<ref name="Niewohner2017">{{cite book|author=Philipp Niewohner|title=The Archaeology of Byzantine Anatolia: From the End of Late Antiquity until the Coming of the Turks|url=https://books.google.com/books?id=cAUmDwAAQBAJ&pg=PA18|date=2017|publisher=Oxford University Press|isbn=978-0190610470|pages=18–|access-date=7 December 2018|archive-date=11 March 2020|archive-url=https://web.archive.org/web/20200311111958/https://books.google.com/books?id=cAUmDwAAQBAJ&pg=PA18|url-status=live}}</ref> coterminous with the [[Anatolian Plateau]]. This traditional geographical definition is used, for example, in the latest edition of ''[[Merriam-Webster's Geographical Dictionary]]''.<ref name="Merriam" /> Under this definition, Anatolia is bounded to the east by the [[Armenian Highlands]], and the [[Euphrates]] before that river bends to the southeast to enter [[Mesopotamia]].<ref name="Mitchell">Stephen Mitchell (1995). ''Anatolia: Land, Men, and Gods in Asia Minor. The Celts in Anatolia and the impact of Roman rule''. Clarendon Press, 266 pp. {{ISBN|978-0198150299}} [https://books.google.com/books?id=pUYtwuve40kC] {{Webarchive|url=https://web.archive.org/web/20170329114033/https://books.google.com/books?id=pUYtwuve40kC|date=29 March 2017}}</ref> To the southeast, it is bounded by the ranges that separate it from the [[Orontes River|Orontes]] valley in [[Syria (region)|Syria]] and the Mesopotamian plain.<ref name="Mitchell"/>
Following the [[Armenian genocide]], [[Western Armenia]] [[Eastern Anatolia Region#Substitution with Armenia|was renamed]] the [[Eastern Anatolia Region]] by the newly established Turkish government.<ref name="Sahakyan">{{cite book|last=Sahakyan|first=Lusine|title=Turkification of the Toponyms in the Ottoman Empire and the Republic of Turkey|year=2010|publisher=Arod Books|location=Montreal|isbn=978-0969987970}}</ref><ref name=":0">{{cite book |last1=Hovannisian |first1=Richard |url=https://books.google.com/books?id=K3monyE4CVQC |title=The Armenian Genocide: Cultural and Ethical Legacies |date=2007 |publisher=Transaction Publishers |isbn=978-1412835923 |location=New Brunswick, NJ |page=3 |access-date=10 September 2015 |archive-date=10 October 2017 |archive-url=https://web.archive.org/web/20171010030024/https://books.google.com/books?id=K3monyE4CVQC |url-status=live }}</ref> In 1941, with the [[First Geography Congress, Turkey|First Geography Congress]] which divided Turkey into [[geographical regions of Turkey|seven geographical regions]] based on differences in climate and landscape, the eastern [[provinces of Turkey]] were placed into the [[Eastern Anatolia Region]],<ref>[http://www.tandfonline.com/doi/abs/10.2167/irgee216.0 A Comparative Analysis Regarding Pictures Included in Secondary School Geography Textbooks Taught in Turkey]. {{Webarchive|url=https://web.archive.org/web/20150413141440/http://www.tandfonline.com/doi/abs/10.2167/irgee216.0 |date=2015-04-13 }}, Okan Yasar and Mehmet Seremet, ''International Research in Geographical and Environmental Education'', 2007.</ref> which largely corresponds to the historical region of [[Western Armenia]] (named as such after the division of [[Kingdom of Armenia (antiquity)|Greater Armenia]] between the [[Roman Empire|Roman]]/[[Byzantine Empire]] (Western Armenia) and [[Sasanian Empire|Sassanid Persia]] ([[Eastern Armenia]]) in 387 AD). Vazken Davidian terms the expanded use of "Anatolia" to apply to territory in eastern Turkey that was formerly referred to as ''Armenia'' (which had a sizeable [[Armenians in the Ottoman Empire|Armenian]] population before the [[Armenian genocide]]) an "ahistorical imposition" and notes that a growing body of literature is uncomfortable with referring to the Ottoman East as "Eastern Anatolia".<ref>Vazken Khatchig Davidian, "Imagining Ottoman Armenia: Realism and Allegory in Garabed Nichanian's Provincial Wedding in Moush and Late Ottoman Art Criticism", p. 7 & footnote 34, in ''Études arméniennes contemporaines'' volume 6, 2015.</ref><ref name="Sahakyan"/><ref name=":0" />
The highest mountain in the [[Eastern Anatolia Region]] (also the highest peak in the [[Armenian Highlands]]) is [[Mount Ararat]] (5123 m).<ref>{{Cite journal| volume = 42| issue = 2| pages = 143–149| last1 = Fevzi Özgökçe| last2 = Kit Tan| last3 = Vladimir Stevanović| title = A new subspecies of Silene acaulis (Caryophyllaceae) from East Anatolia, Turkey| journal = Annales Botanici Fennici|year = 2005| jstor = 23726860}}</ref> The [[Euphrates]], [[Aras (river)|Aras]], [[Karasu (Euphrates)|Karasu]] and [[Murat river]]s connect the Armenian Highlands to the [[South Caucasus]] and the Upper Euphrates Valley. Along with the [[Çoruh]], these rivers are the longest in the Eastern Anatolia Region.<ref name=palumbi>{{Cite journal| doi = 10.1093/oxfordhb/9780195376142.013.0009| last = Palumbi| first = Giulio| title = The Chalcolithic of Eastern Anatolia| journal = The Oxford Handbook of Ancient Anatolia| volume = 1| access-date = 6 May 2018| date = 5 September 2011| url = http://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780195376142.001.0001/oxfordhb-9780195376142-e-9| editor1-last = McMahon| editor1-first = Gregory| editor2-last = Steadman| editor2-first = Sharon| archive-date = 12 May 2018| archive-url = https://web.archive.org/web/20180512155433/http://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780195376142.001.0001/oxfordhb-9780195376142-e-9| url-status = live}}</ref>