Download Sintra-Cascais Natural Park wallpapers in 480X720, 960X1440, 3500X5200 resolutions for iPhone, Android, tablets, etc. The Sintra-Cascais Natural Park is a park on the Portuguese Riviera, one of the 13 Natural Parks of Portugal. While only established in 1994 as a Natural Park by the Portuguese Government, it has been protected since 1981.