Built by King Philippe II, it was designed as a defensive structure for the city and served as its main fortification until the 19th century. It is one of the oldest surviving monuments in Paris and has been designated an historical monument since 1840.
The enclosure stretches about 2 kilometres around parts of today’s 1st, 4th and 5th arrondissements. Its walls are made from limestone blocks connected with mortar and stand at an average height of 8 meters (26 feet). The wall also features 11 towers located along its length – each tower measuring between 9–12 meters (30–40 feet) tall – which were used to defend against attackers or house troops during sieges.
In addition to its military purpose, The Enclosure had other uses throughout history too; it served as a prison for political prisoners during Louis XIV’s reign and later became part of a large public park known as ‘Le Jardin des Plantes’ when it opened in 1793. Today visitors can still see some sections of this ancient wall while exploring Le Jardin des Plantes or walking through certain streets in Paris such as rue de la Huchette near Place Maubert Square or Rue Saint Jacques near Place Monge Square.
Although much has changed over time, many parts remain intact due to extensive restoration efforts throughout the centuries; particularly after World War II when much damage had occurred due to German bombardment on nearby areas such as Montparnasse Tower, which stands close by today.