Ancient Monuments

History on the Ground

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Mounds on the Island

A Scheduled Monument in Martletwy, Pembrokeshire (Sir Benfro)

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Latitude: 51.7898 / 51°47'23"N

Longitude: -4.8531 / 4°51'11"W

OS Eastings: 203324

OS Northings: 213983

OS Grid: SN033139

Mapcode National: GBR CQ.YJVK

Mapcode Global: VH1RN.T8PR

Entry Name: Mounds on the Island

Scheduled Date: 17 June 1952

Source: Cadw

Source ID: 462

Cadw Legacy ID: PE276

Schedule Class: Unassigned

Category: Mound

Period: Medieval

County: Pembrokeshire (Sir Benfro)

Community: Martletwy

Traditional County: Pembrokeshire


The monument consists of two mounds, artificial elevations of earth and stones thought to date from the 17th-18th centuries and to be a landscape feature of Slebech Park and associated with Slebech Hall The mounds are located on a little peninsula jetting out into the Eastern Cleddau which becomes an island at high tide. The south west mound has an oval flat-topped summit, c.30m E-W by 21m, the north east mound has a tapering oval flat-topped summit, c.28m NE-SW by 13.5m. Both mounds are apparently stone revetted and show traces of masonry foundations.

The monument is of national importance for its potential to enhance our knowledge of construction techniques. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. A mound may be part of a larger cluster of monuments and their importance can further enhanced by their group value.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw

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