Geograph - photograph every grid square

This National Trail is 184 miles (294 km) long, following the River Thames from its source in the Cotswolds almost to the sea, finishing at the Thames Barrier in Greenwich.
The trail keeps to the banks of the river most of the route.
Website: Link

The Thames Cycle Route is part of the National Cycle Network. The Cycle Route stretches from Dartford up to Oxford along the banks of the River Thames.

This follows the majority of the Thames Path, but does divert in various sections. Especially where the Path follows a footpath only route. It also links National Cycle Route 1 (east of London) with National Cycle Route 4 (west of London).

Starting at the Thames at Erith and finishing on the opposite north bank at Coldharbour, the Loop (London Outer Orbital Path) is 150 miles long, passing through numerous woods, commons and parks and on waterside paths alongside the Grand Union Canal and London rivers such as the Colne, Crane, Cray, Darent and Ingrebourne.

The River Thames rises at Thames Head in Gloucestershire on the slopes of the Cotswolds and flows generally eastward to its mouth near Southend in Essex. At 215 miles long it is one of the longest rivers in Britain, and the longest entirely within England. It is one of the most important rivers in Britain. Link