Kent is a county in South East England and one of the home counties. It borders Greater London to the north-west, Surrey to the west and East Sussex to the south-west, Essex to the north along the estuary of the River Thames (connected by land via High Speed 1 and the Dartford Crossing), and the French department of Pas-de-Calais (through the Channel Tunnel). The county town is Maidstone. It is the fifth most populous county in England, the most populous non-Metropolitan county and the most populous of the home counties.