Hertfordshire is located in the south east of England, just north of London and south of Bedfordshire and Buckinghamshire. The county town of Hertfordshire is Hertford and there are a total of 5 cities and towns in the county, which are Stevenage, Watford, Hemel Hempstead, St Albans and Welwyn Garden City. The largest city in Hertfordshire with the largest population is Watford with 54,200 people living there as of the 2011 census. Hertfordshire has an area of 438 square miles, which makes it one of the smaller counties in the UK. There are a number of important historical sites within Hertfordshire, including several castles. Three national parks can also be found in Hertfordshire: Broxbourne, the Lee Valley and the North Hertfordshire.