The City of Baku is renowned for its gardens, fountains and attractive seaside. Open spaces within the citys borders function as "green lungs", the Caspian Sea as well as unsettled hills around the City of Baku bring fresh air into the city. Though technically the easternmost extension of the Caucasus Mountains, the landscape is only mildly hilly, a gently undulating plain that ends in a long spit of sand dunes.