The River Medway
flows from Turners Hill, in West Sussex
, through Tonbridge
, to the River Thames
. From 1746
the limit of navigation was Tonbridge, but the channel was improved to Leigh in 1828
. Small craft such as canoes can sometimes travel as far as Penshurst. The lowest (tidal) lock, opened in 1792
, is at Allington. The stretch from Leigh to Allington is known as the Medway Navigation, and is 19 miles (31 km) long. The mouth of the river is defined by Garrison Point, between the Isle of Sheppey
and the Isle of Grain.
The Medway divides the county of Kent into two parts. Traditionally, the western part was administered from Maidstone, its inhabitants being called Kentishmen, while the eastern part was administered from Canterbury, its inhabitants being called Men of Kent. The county was united in 1814, with Maidstone as the county town.
A new 1.3km railway bridge, with a central span of 152m, was built in 2003 for the Channel Tunnel Rail Link project.