Almeirim (Portuguese pronunciation: [ɐɫmɐjˈɾĩ]) is a city and a municipality in Santarém District, Portugal. The population in 2011 was 23,376, in an area of 222.12 km². The city proper had a population of 10,520 in 2001.
There are vestiges of mid-Paleolithic to Mesolithic period along the territory, including traces from Neolithic, Calcolithic and Bronze Age remnants. The Iron Age also marked this region, with archaeological excavations unearthing settlements and artefacts.
Roman legions of Décimo Junius Brutus occupied the territory, following the Tagus upstream and disembarking in Santarém, where their left their marks. These, along with other groups, occupied arable lands, beginning in the first century A.D. This included the development of agriculture (particularly wheat and olive orchards) and raising of cattle, supporting the establishment of Almeirim along the margins of the Tagus.
References to this municipality, began appearing in the 14th century. With rich lands, the territory supported hunting, extending to Santarém, and proximities of the Tagus and Lisbon. This easy access, made Almeirim a preferred place for the Kings of the second Dynasty, and a winter place frequented by members of Corte, becoming known as the Sintra of Winter. Almeirim, therefore, became an ideal place for relaxation, palace intrigue and romantic encounters in the royal gardens, mixed with resolutions of important negotiations.