Sintra is known for its many 19th-century Romantic architectural monuments, which has resulted in its classification as a UNESCO World Heritage Site. Although its heritage in buildings and nature is the most visible face of the historic individuality of Sintra, a whole literary heritage has made the area a legendary reference in Portuguese culture. It has become a major tourist centre, visited by many day-trippers who travel from the urbanized suburbs and capital of Lisbon. In addition to the Sintra Mountains and Sintra-Cascais Nature Park, the parishes of the town of Sintra are dotted by royal retreats, estates, castles and other buildings, including the Castelo dos Mouros, the Pena National Palace and the Sintra National Palace.The Mediterranean climate, influenced by the Atlantic, is typical of continental Portugal, characterized by moderate temperatures and wet winters. Although the climate in area of Cabo da Roca is semi-arid, the Sintra Mountains is considered moderately humid. In fact, precipitation in the mountains are more elevated then in the areas circling the mountains. The position of the municipality, within the natural landscape of the Sintra Mountains (consisting of an exuberant natural patrimony), is influenced by the existence of a micro-climate.[4][6] For different reasons (the climate here has been proportioned by the Sintra Mountains; the fertility of the lands deposited; and its relative proximity to the Tagus estuary) the region has attracted a large early settlement. Due to its micro-climate, a huge park has developed, full of rich, dense foliage, with a rich botanical diversity, constituting groups of a national forest.