The navigation begins in Bishop's Stortford, just to the south of the A1250 Hockerill Bridge.
It receives its water supply from the upper River Stort, which rises as a series of streams near Langley, some 11 miles (18 km) to the north.
Nearby and to the east is Bishop's Stortford railway station, on the London Liverpool Street to Kings Lynn line.
Both bear south, and the railway crosses to the west bank.
South Mill lock marks the start of the descent, and beyond it are watermeadows and Rushy Mead Nature Reserve, an 11.5-acre (4.7 ha) site run by Essex Wildlife Trust which was the location of a sewage pumping station prior to 1950.
After Twyford Lock, it passes below Wallbury Camp, on the east bank.
This is an iron-age hill fort, and is a scheduled ancient monument.
Spellbrook Lock and Tadnambury Lock follow shortly afterwards.
The river flows around Tadnambury Lock in a large loop, on which Hallingbury Mill is located.
It was built in 1874, and there is a granary built on the site of the original mill which was demolished in 1885.
The breast-shot waterwheel is 7 feet (2.1 m) wide and 16 feet (4.9 m) in diameter.
The Grade II* listed mill was restored in the late 1960s, and is now a hotel and bistro.
The railway crosses back to the east bank, as the navigation enters Sawbridgeworth.

Sawbridgeworth Lock is located on the northern edge of the town, where both the timber-framed and weatherboarded mill house, and the nearby grain store, date from the 18th century and are Grade II listed.
Sheering Mill Lock is to the east, where the navigation is sandwiched between the village of Lower Sheering and the town.
The mill house here dates from the 17th century, and is timber framed with exterior plasterwork.
It was extended in the 19th and 20th centuries, and contains reproduction features, which make the historical evidence more difficult to decipher.
Below Sawbridgeworth is Feakes Lock, where the navigation turns towards the south-west.
As it does so, it forms the eastern edge of the Pishiobury Estate, a country house and landscaped park containing gardens from the 16th century and later.
The Grade II listed grounds include formal canals, and the landscaping is attributed to Capability Brown.

On the northern edge of Harlow, it passes under the A1184 road, which is immediately followed by Harlow Lock.
The adjacent mill probably dates from the 17th century, but gives few clues to its age.
It is now a restaurant.
The railway separates the navigation from the town.
There are no significant buildings at Latton Lock or Burnt Mill Lock, but there is a mill building at Parndon Lock, dating from the mid- or late-19th century.
It used both water power and steam power, although none of the machinery survives except a water turbine.
The mill house is somewhat older, dating from the mid-18th century, and is a three-storey brick building, the front of which is rendered.

Near Hunston Mill Lock is the brick base of a watermill, which was demolished in 1902, and a brick bridge with abutments.
There was a mill on the site in 1066.
Some 19th century cast-iron sluices still control water flow through the site.
The adjacent mill house with its stables, coach house and walls are all Grade II listed.
The house dates from the 17th century, although it was faced with brick and extended in the 19th century, and extended again in 1912.
To the west is Briggens, an 18th-century house with landscaped gardens designed by Charles Bridgeman around 1720, which also has some Edwardian pleasure gardens.
The house is now a hotel, and there is a golf course in part of the gardens, although most of the 18th century landscape features have been retained.

Just after Roydon Lock, the railway crosses from the south bank to the north on a low bridge.
Roydon railway station is very close to the navigation, although its attractive timber-framed and plastered buildings dating from 1844 face away from the river.
The navigation now enters the Lee Valley Regional Park and threads its way between flooded gravel pits and Rye Meads sewage treatment works to the north.
Just above Br
The navigation begins in Bishop's Stortford, just to the south of the A1250 Hockerill Bridge. It receives its water supply from the upper River Stort, which rises as a series of streams near Langley, some 11 miles (18 km) to the north. Nearby and to the east is Bishop's Stortford railway station, on the London Liverpool Street to Kings Lynn line. Both bear south, and the railway crosses to the west bank. South Mill lock marks the start of the descent, and beyond it are watermeadows and Rushy Mead Nature Reserve, an 11.5-acre (4.7 ha) site run by Essex Wildlife Trust which was the location of a sewage pumping station prior to 1950. After Twyford Lock, it passes below Wallbury Camp, on the east bank. This is an iron-age hill fort, and is a scheduled ancient monument. Spellbrook Lock and Tadnambury Lock follow shortly afterwards. The river flows around Tadnambury Lock in a large loop, on which Hallingbury Mill is located. It was built in 1874, and there is a granary built on the site of the original mill which was demolished in 1885. The breast-shot waterwheel is 7 feet (2.1 m) wide and 16 feet (4.9 m) in diameter. The Grade II* listed mill was restored in the late 1960s, and is now a hotel and bistro. The railway crosses back to the east bank, as the navigation enters Sawbridgeworth.
Sawbridgeworth Lock is located on the northern edge of the town, where both the timber-framed and weatherboarded mill house, and the nearby grain store, date from the 18th century and are Grade II listed. Sheering Mill Lock is to the east, where the navigation is sandwiched between the village of Lower Sheering and the town. The mill house here dates from the 17th century, and is timber framed with exterior plasterwork. It was extended in the 19th and 20th centuries, and contains reproduction features, which make the historical evidence more difficult to decipher. Below Sawbridgeworth is Feakes Lock, where the navigation turns towards the south-west. As it does so, it forms the eastern edge of the Pishiobury Estate, a country house and landscaped park containing gardens from the 16th century and later. The Grade II listed grounds include formal canals, and the landscaping is attributed to Capability Brown.
On the northern edge of Harlow, it passes under the A1184 road, which is immediately followed by Harlow Lock. The adjacent mill probably dates from the 17th century, but gives few clues to its age. It is now a restaurant. The railway separates the navigation from the town. There are no significant buildings at Latton Lock or Burnt Mill Lock, but there is a mill building at Parndon Lock, dating from the mid- or late-19th century. It used both water power and steam power, although none of the machinery survives except a water turbine. The mill house is somewhat older, dating from the mid-18th century, and is a three-storey brick building, the front of which is rendered.
Near Hunston Mill Lock is the brick base of a watermill, which was demolished in 1902, and a brick bridge with abutments. There was a mill on the site in 1066. Some 19th century cast-iron sluices still control water flow through the site. The adjacent mill house with its stables, coach house and walls are all Grade II listed. The house dates from the 17th century, although it was faced with brick and extended in the 19th century, and extended again in 1912. To the west is Briggens, an 18th-century house with landscaped gardens designed by Charles Bridgeman around 1720, which also has some Edwardian pleasure gardens. The house is now a hotel, and there is a golf course in part of the gardens, although most of the 18th century landscape features have been retained.
Just after Roydon Lock, the railway crosses from the south bank to the north on a low bridge. Roydon railway station is very close to the navigation, although its attractive timber-framed and plastered buildings dating from 1844 face away from the river. The navigation now enters the Lee Valley Regional Park and threads its way between flooded gravel pits and Rye Meads sewage treatment works to the north. Just above Br
Stort Navigation