Nine Barrow Down is an elongated hill forming the northern ridge of the Purbeck Hills

Purbeck Hills

The Purbeck Hills and South Dorset Downs are a ridge of chalk downs in Dorset, England. The hills extend from the Dorset Downs west of Dorchester, where the River Frome begins to form a valley dividing them from the larger area of downland to the north. The ridge then runs east through the Isle...

 on the Isle of Purbeck

Isle of Purbeck

The Isle of Purbeck, not a true island but a peninsula, is in the county of Dorset, England. It is bordered by the English Channel to the south and east, where steep cliffs fall to the sea; and by the marshy lands of the River Frome and Poole Harbour to the north. Its western boundary is less well...

 in Dorset

Dorset

Dorset , is a county in South West England on the English Channel coast. The county town is Dorchester which is situated in the south. The Hampshire towns of Bournemouth and Christchurch joined the county with the reorganisation of local government in 1974...

, 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...

. The chalk down

Downland

A downland is an area of open chalk hills. This term is especially used to describe the chalk countryside in southern England. Areas of downland are often referred to as Downs....

 is part of the extensive Southern England Chalk Formation

Southern England Chalk Formation

The Chalk Formation of Southern England is a system of chalk downland in the south of England. The formation is perhaps best known for Salisbury Plain, the location of Stonehenge, the Isle of Wight and the twin ridgeways of the North Downs and South Downs....

. The eastern end of the ridge, which carries the highest point, is also sometimes known as Godlingston Hill. The col of the railway

Swanage Railway

The Swanage Railway is a long heritage railway in the Purbeck district of Dorset, England. The railway follows the route of the Purbeck branch line between Norden railway station, Corfe Castle railway station, Harman's Cross railway station, Herston Halt railway station and Swanage...

 cutting at Harman's Cross

Harman's Cross

Harman's Cross is a small village on the Isle of Purbeck, in the county of Dorset in the south of England. It is situated on the A351 road between Swanage and Corfe Castle.The village is located in the civil parish of Worth Matravers...

 means that it has sufficient relative height that it qualifies as a Marilyn

Marilyn (hill)

A Marilyn is a mountain or hill in the United Kingdom, Republic of Ireland or Isle of Man with a relative height of at least 150 metres , regardless of absolute height or other merit...

.

The hill has views to the north across Poole Harbour

Poole Harbour

Poole Harbour is a large natural harbour in Dorset, southern England, with the town of Poole on its shores. The harbour is a drowned valley formed at the end of the last ice age and is the estuary of several rivers, the largest being the Frome. The harbour has a long history of human settlement...

 and to the south the other ridge of the Purbeck Hills, including Swyre Head

Swyre Head

Swyre Head is the highest point of the Purbeck Hills and the Isle of Purbeck in Dorset, on the south coast of England. The hill Swyre Head lies about two kilometres southwest of the village Kingston, about five kilometres south of Corfe Castle and eight kilometres west of Swanage.Although not very...

. To the south-east Swanage

Swanage

Swanage is a coastal town and civil parish in the south east of Dorset, England. It is situated at the eastern end of the Isle of Purbeck, approximately 10 km south of Poole and 40 km east of Dorchester. The parish has a population of 10,124 . Nearby are Ballard Down and Old Harry Rocks,...

 and its Bay can be seen. Along the ridge there are nine barrow

Tumulus

A tumulus is a mound of earth and stones raised over a grave or graves. Tumuli are also known as barrows, burial mounds, Hügelgrab or kurgans, and can be found throughout much of the world. A tumulus composed largely or entirely of stones is usually referred to as a cairn...

s — stone age burial mounds — hence the name.

Until recently the hill was topped with a trig point

Trig point

A triangulation station, also known as a triangulation pillar, trigonometrical station, trigonometrical point, trig station, trig beacon or trig point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity...

, but this has been removed by the farmer with the permission of Ordnance Survey

Ordnance Survey

Ordnance Survey , an executive agency and non-ministerial government department of the Government of the United Kingdom, is the national mapping agency for Great Britain, producing maps of Great Britain , and one of the world's largest producers of maps.The name reflects its creation together with...

: the trig point and its concrete base can be seen on its side just to the south of the bridleway. The highest point is within a field marked "No public access".

Ecologically the ridge is largely calcareous grassland

Calcareous grassland

Calcareous grassland is an ecosystem associated with thin basic soil, such as that on chalk and limestone downland. Plants on calcareous grassland are typically short and hardy, and include grasses and herbs such as clover...

 grazed by cattle, sheep and rabbits, with limited arable

Arable land

In geography and agriculture, arable land is land that can be used for growing crops. It includes all land under temporary crops , temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow...

use.
It is also the site for the 2 kW Heart South Coast Transmitter on 102.3 and for the NOW Digital Multiplexes.