The region of Tuscany includes seven coastal islands and is Italy's fifth largest region. It is bordered to the northwest by Liguria, the north by Emilia-Romagna, Umbria to the east and Lazio to the south. To the west is the Tyrrhenian Sea which gives the area a warm mediterranean climate. The terrain is quite hilly (over 68% of the terrain), progressing inward to the Apennine Mountains along the border with Emilia-Romagna. The hills have a tempering effect on the summertime heat, with many vineyards planted on the higher elevations of the hillsides.