<P> The major trade was salt . The arrival of the Trent and Mersey Canal at Anderton in 1773 was detrimental to the salt trade at first, but ultimately beneficial, as salt was tipped down chutes from the canal into barges on the river navigation . Access to the river was improved in 1810 by the Weston Canal, which provided a link to Weston Point, where boats could reach the River Mersey at most states of the tide, as the water was deeper . The navigation was completely reconstructed between 1870 and 1900, with the original locks being replaced by five much larger locks, capable of handling 1000 - tonne coasters . With the opening of the Manchester Ship Canal, a new lock was constructed at Weston Marsh, which gave direct access to the ship canal without having to pass through the docks at Weston Point . All water from the river entered the canal nearby, and any surplus was released into the Mersey through the Weaver sluices, which were located just upstream of the junction . </P> <P> A notable feature is the Anderton Boat Lift, which is near Northwich, and links the Weaver with the Trent and Mersey Canal some 50 feet (15 m) above . It was opened in 1875, to allow canal boats to reach the Weaver, and although closed on safety grounds in 1983, it was refurbished and reopened in 2002 . Many of the structures of the navigation are of historical importance, and are grade II listed . They include the Hayhurst swing bridge and Northwich Town bridge, which are believed to be the earliest swing bridges powered by electricity . Both have a sectional pontoon, which is immersed in the river and carries about 80 per cent of the weight of the bridge . Dutton Horse Bridge, which carries the towpath over the weir stream at Dutton, is one of the earliest surviving laminated timber structures . Dutton railway viaduct, which was built by Joseph Locke and George Stephenson for the Grand Junction Railway, is grade II * listed, and a civic celebration was held on its completion, as there had been no deaths and no serious injuries to the workers during its construction . </P> <P> The River Weaver is more than 50 miles (80 km) long . From its source in the hills of west Cheshire just south of Peckforton Castle, and within a few hundred metres of the source of the River Gowy it initially flows in a south - easterly direction towards the border with Shropshire, fed by tributaries some of which rise in north Shropshire . The first of three canal crossings occurs just before the village of Wrenbury, when the Llangollen Canal crosses its course . After flowing through the village, it passes to the west of the Cheshire village of Audlem, where it starts to flow approximately northwards across the Cheshire Plain . Shortly afterwards, the Shropshire Union Canal is carried over it on Moss Hall aqueduct . The first significant town on the river is the market town of Nantwich, where a watermill was a feature from the 13th century; 100m further north, an early 19th - century stone bridge, with a single span, crosses the river . Continuing northwards, it passes under the Middlewich Branch of the Shropshire Union Canal before the village of Church Minshull . The aqueduct carrying the canal was designed by Thomas Telford and was built of brick with stone bands between 1827 and 1833 . The river flows through a central arch, and there are flood relief arches on each side of the channel . The two waterways run roughly parallel for several miles . They diverge near Winsford, the current head of navigation, and at Northwich the river turns to flow north - west across north Cheshire . </P> <P> Below Winsford, the course of the river has been altered several times, by the construction of cuts and locks, to enable small ships to trade on it . The river formerly joined the River Mersey at Weston Marsh, but since the construction of the Manchester Ship Canal, begun in 1887, it has flowed into the canal, from where surplus water enters the Mersey by the Weaver sluices, just upstream of the junction . The tidal river section below Frodsham has been bypassed by the Weston Canal since 1810, and is no longer navigable, as Frodsham Lock is derelict . </P>

Where does the river weaver start and end
find me the text answering this question