The River Amber is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in Derbyshire

Derbyshire

Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 which rises close to the village of Ashover

Ashover

Ashover is a village in the English county of Derbyshire. It is in the North East Derbyshire district of the county. It sits in a picturesque valley, not far from the town of Matlock and the Peak District national park. The centre of the village is a conservation area. The River Amber flows through...

, near Clay Cross

Clay Cross

Clay Cross is a former mining town and civil parish in the North East Derbyshire district of Derbyshire, England, about six miles south of Chesterfield. It is directly on the A61, the former Roman road Ryknield Street...

, and flows southwards through Ogston Reservoir

Ogston Reservoir

Ogston Reservoir is a reservoir operated by Severn Trent Water in Derbyshire. It is near the villages of Brackenfield, Ashover and Clay Cross....

 to Pentrich then westwards to join the River Derwent

River Derwent, Derbyshire

The Derwent is a river in the county of Derbyshire, England. It is 66 miles long and is a tributary of the River Trent which it joins south of Derby. For half its course, the river flows through the Peak District....

 at Ambergate

Ambergate

Ambergate is a village in Derbyshire, England, where the River Amber joins the River Derwent.Until the early nineteenth century it was known as Toadmoor, with no more than a few artisans' cottages. The southerly half of the village was still shown as such on the Ordnance Survey's maps.It is about ...

. It gives its name to the local government district

Non-metropolitan district

Non-metropolitan districts, or colloquially shire districts, are a type of local government district in England. As created, they are sub-divisions of non-metropolitan counties in a so-called "two-tier" arrangement...

 and borough

Borough

A borough is an administrative division in various countries. In principle, the term borough designates a self-governing township although, in practice, official use of the term varies widely....

 of Amber Valley

Amber Valley

Amber Valley is a local government district and borough in Derbyshire, England. It takes its name from the River Amber and covers a semi-rural area with a number of small towns formerly based around coal mining and engineering...

.

Like many such rivers flowing from the Derbyshire, it gave a good supply for water mills, many of them for crushing locally mined and quarried minerals, such as limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

.

The river valley also provided a route for the Cromford Canal

Cromford Canal

The Cromford Canal ran 14.5 miles from Cromford to the Erewash Canal in Derbyshire, England with a branch to Pinxton. Built by William Jessop with the assistance of Benjamin Outram, its alignment included four tunnels and 14 locks....

 at the southern end and the North Midland Railway

North Midland Railway

The North Midland Railway was a British railway company, which opened its line from Derby to Rotherham and Leeds in 1840.At Derby it connected with the Birmingham and Derby Junction Railway and the Midland Counties Railway at what became known as the Tri Junct Station...

 to travel northwards till it passed under Clay Cross

Clay Cross

Clay Cross is a former mining town and civil parish in the North East Derbyshire district of Derbyshire, England, about six miles south of Chesterfield. It is directly on the A61, the former Roman road Ryknield Street...

 via the Clay Cross Tunnel

Clay Cross Tunnel

Clay Cross Tunnel is a 1,784-yard tunnel on the former North Midland Railway line near Clay Cross in Derbyshire, England now part of the Midland Main Line....

, enter the valley of the River Rother

River Rother, South Yorkshire

The River Rother is a river in the northern midlands of England, after which the town of Rotherham and the Rother Valley parliamentary constituency are named. It rises near Clay Cross in Derbyshire, and flows through the centre of Chesterfield, where it feeds the Chesterfield Canal...

 and then north to Chesterfield

Chesterfield

Chesterfield is a market town and a borough of Derbyshire, England. It lies north of Derby, on a confluence of the rivers Rother and Hipper. Its population is 70,260 , making it Derbyshire's largest town...

.