Details

The monument includes three separate areas which consist of the remains of a
medieval moat, fishponds, and quarries associated with Blackburn Hall. The
moat is almost circular, measuring about 80m east-west by 75m north-south.
The central island is surrounded by a 12m wide moat on all but its south-east
arm which is larger, forming a pond up to 20m wide. There is a cobbled ramp
leading into this pond, enabling livestock to be led into the water to drink.
The moat is about 3.0m deep and permanent standing water is found in the ditch
on the eastern arm. A bank flanks the external edge of the moat on its
northern and western arms. The bank is about 5m wide and less than 0.5m high.
Causeways cross the moat to the east and west. The moat island includes a
raised platform, 0.5-1.0m high, with a central hollow in which stands
Blackburn Hall, a Grade II listed building. The Hall itself incorporates part
of a 13th century aisled building with most of the rest of the structure
dating to the post-medieval period. Foundations of ancillary buildings
associated with the Hall were excavated in 1990 in advance of construction of
a new swimming pool. A pair of fishponds are located some 10m to the south-
east. They are approximately 32m in length by 12m wide and up to 2m deep,
lying to either side of a small banked island; their northern and southern
ends are connected by leats. The ponds are surrounded to the north and east
by a ditch, which is known from documentary sources to have been part of a
much larger enclosure which extended to the south. The enclosure was surveyed
in 1920 but has since been levelled by ploughing. Situated to the north-east
of the moat are two quarries. These consist of two water-filled hollows, 30m
by 12m in size, which are believed to be very deep. They are identified as
the likely source of building materials used in the construction of the Hall
and which were later maintained as a source of water.
Blackburn Hall lies close to other medieval monuments, including another
moated site at Bletsoe less than 1km to the west, and there is a motte and
bailey castle at the village of Thurleigh, 1.5km distant.
Made trackways and upstanding buildings, including the Grade II listed hall
and sheds near the quarries, are excluded from the scheduling although the
ground beneath them is included. The newly constructed swimming pool within
the grounds of the main house is also excluded.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

Around 6,000 moated sites are known in England. They consist of wide ditches,
often or seasonally water-filled, partly or completely enclosing one or more
islands of dry ground on which stood domestic or religious buildings. In some
cases the islands were used for horticulture. The majority of moated sites
served as prestigious aristocratic and seigneurial residences with the
provision of a moat intended as a status symbol rather than a practical
military defence. The peak period during which moated sites were built was
between about 1250 and 1350 and by far the greatest concentration lies in
central and eastern parts of England. However, moated sites were built
throughout the medieval period, are widely scattered throughout England and
exhibit a high level of diversity in their forms and sizes. They form a
significant class of medieval monument and are important for the understanding
of the distribution of wealth and status in the countryside. Many examples
provide conditions favourable to the survival of organic remains.

Blackburn Hall moated site is an above average example of a Bedfordshire moat
with well-preserved archaeological structures. Although partially excavated,
the monument displays a wide diversity of surviving features including
fishponds and a rare association with quarry pits.

Source: Historic England

Sources

Books and journals
Beds Historical Soc. Data, (1977)
The Victoria History of the County of : Volume III, (1912)
Wadmore, B, The Earthworks of Bedfordshire, (1920)
Other
P.A.S., Ordnance Survey Record,
P.A.S., Ordnance Survey Record, (1973)

Source: Historic England