The Lisbon Naval Base (Portuguese: Base Naval de Lisboa), is the main installation and operational base of the Portuguese Navy. Being located at the former Royal Estate of Alfeite on the south bank of the Tagus river's huge estuary, near the city of Almada, the installation is commonly referred to as the Alfeite Naval Base.Most of the Portuguese Naval fleet ships are based at Alfeite, as well as many of its administrative, training and support services.