Ancient Monuments

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Porth Mawr

A Scheduled Monument in Crickhowell (Crughywel), Powys

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Latitude: 51.8604 / 51°51'37"N

Longitude: -3.1376 / 3°8'15"W

OS Eastings: 321754

OS Northings: 218592

OS Grid: SO217185

Mapcode National: GBR F0.SY3Q

Mapcode Global: VH6CH.KHMN

Entry Name: Porth Mawr

Scheduled Date:

Source: Cadw

Source ID: 786

Cadw Legacy ID: BR114

Schedule Class: Domestic

Category: Gatehouse

Period: Post Medieval/Modern

County: Powys

Community: Crickhowell (Crughywel)

Built-Up Area: Crickhowell

Traditional County: Brecknockshire


The monument consists of the remains of a 15th century gatehouse with a single carriageway and room above. The gateway is positioned within a stone embattled wall and is turreted in a Tudor style. It has Tudor arches and an upper chamber lit by two hooded windows, an octagonal chimney and a battlement parapet. A spiral staircase leads to the first floor and the roof on the NE corner of the gatehouse, is lit by a small rectangular window and exits to the roof from a stair turret. In the interior the ribbed vault with bosses is of early 19th century date. The arch facing the road has weather mouldings, hood and stops, while the house-facing arch is chamfered. The gateway was built by the Herbert family during the reign of Henry VIII as the entrance to their mansion, Cwrt Carw. The Tudor mansion was demolished in the early 19th century and replaced by a Regency style manor house.

The monument is of national importance for its potential to enhance our knowledge of entrance architecture. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The structure itself may be expected to contain archaeological information concerning chronology and building techniques. A gatehouse 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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