Trident-armed ballistic missile submarines that comprise the Britain's nuclear deterrent. Scapa Flow was the major Fleet base for the Royal Navy until 1956. Scotland's Scapa Flow was the main base for the Royal Navy in the 20th century. As the Cold War intensified in 1961, the United States deployed Polaris ballistic missiles, and submarines, in the Firth of Clyde's Holy Loch. Public protests from CND campaigners proved futile. The Royal Navy successfully convinced the government to allow the base because it wanted its own Polaris submarines, and it obtained them in 1963. The RN's nuclear submarine base opened with four Polaris submarines at the expanded Faslane Naval Base on the Gare Loch. The first patrol of a Trident-armed submarine occurred in 1994, although the US base was closed at the end of the Cold War. A single front-line Royal Air Force base is located in Scotland. RAF Lossiemouth, located in Moray, is the most northerly air defence fighter base in the United Kingdom and is home to three fast-jet squadrons equipped with the Eurofighter Typhoon. Education The Scottish education system has always been distinct from the rest of the United Kingdom, with a characteristic emphasis on a broad education. In the 15th century, the Humanist emphasis on education cumulated with the passing of the Education Act 1496, which decreed that all sons of barons and freeholders of substance should attend grammar schools to learn "perfyct Latyne", resulting in an increase in literacy among a male and wealthy elite. In the Reformation, the 1560 First Book of Discipline set out a plan for a school in every parish, but this proved financially impossible. In 1616 an act in Privy council commanded every parish to establish a school. By the late seventeenth century there was a largely complete network of parish schools in the lowlands, but in the Highlands basic education was still lacking in many areas. Education remained a matter for the church rather than the state until the Education (Scotland) Act 1872. The Curriculum for Excellence, Scotland's national school curriculum, presently provides the curricular framework for children and young people from age 3 to 18. All 3- and 4-year-old children in Scotland are entitled to a free nursery place. Formal primary education begins at approximately 5 years old and lasts for 7 years (P1–P7); children in Scotland study National Qualifications of the Curriculum for Excellence between the ages of 14