West Sussex · South Downs · Historic Parkland

Arundel Park: Hiorne Tower, Swanbourne Lake & South Downs History

Explore the historic parkland north of Arundel Castle: open downland, deep wooded valleys, old estate walls, Swanbourne Lake and the remarkable eighteenth-century Hiorne Tower.

Grade II* The wider Arundel Castle park and garden landscape is registered for its special historic interest.
c. 478 ha The registered landscape includes gardens, parkland and woodland.
1796 Hiorne Tower was built as a dramatic architectural folly within the park.
1797 Swanbourne Lake was enlarged from an earlier mill pond.

Arundel Park occupies the rolling chalk landscape immediately north of Arundel Castle, extending deep into the South Downs.

Its combination of open pasture, wooded slopes, dry valleys, historic estate buildings and panoramic views towards the River Arun makes it one of the most distinctive historic landscapes in West Sussex.

The park seen today is not simply natural countryside. It reflects centuries of estate ownership, designed landscaping, woodland planting and the deliberate creation of views and architectural landmarks.

A Historic Designed Landscape

The parkland surrounding Arundel Castle has medieval origins, but the large New or Great Park seen today was principally created during the late eighteenth and early nineteenth centuries.

Former agricultural and warren land was incorporated into an extensive park designed to provide a grand landscape setting for the castle.

Historic woodland, open grassland, plantations, estate walls and architectural features were combined to create the landscape.

Inside the South Downs

Arundel Park lies on a high north-to-south ridge of the South Downs. Deep dry valleys and steep wooded slopes cut through the chalk landscape.

To the east, the land falls sharply towards the level floodplain of the River Arun.

This dramatic change in elevation creates extensive views over the Arun Valley towards the Downs on the opposite side of the river.

More than countryside: Arundel Park is a designed historic landscape in which natural South Downs topography was combined with planting, estate architecture, walls, roads and carefully positioned landmarks.

A Short History of Arundel Park

Medieval period Deer parks already existed within the wider Arundel estate. The Home Park later developed into the Little or Castle Park.
1067 onwards The history of the estate became closely connected with Arundel Castle and the noble families who controlled the Honor of Arundel.
Late 18th century The New or Great Park began to take its modern form from former arable and warren land.
1789–1793 Considerable areas north of the existing park were incorporated into the enlarged designed landscape.
1790s A major programme of enclosure and woodland planting was undertaken, including extensive use of beech.
1796 – Hiorne Tower The triangular Gothic folly designed by Francis Hiorne was built on high ground within the park.
1797 – Swanbourne Lake The lake was enlarged from an earlier mill pond within the wooded valley.
Early 19th century The park's enclosing flint wall and planting continued to develop.
1987 The Great Storm caused extensive damage to plantations within the park. Much woodland was subsequently replanted, particularly with beech.
Today The landscape forms part of the South Downs National Park and remains closely associated with Arundel Castle and the Norfolk estate.

Hiorne Tower

One of the most memorable structures in Arundel Park is Hiorne Tower, standing on high ground north-west of the castle.

The tower was built in 1796 and takes its name from its architect, Francis Hiorne.

It is triangular in plan, built in flint and stone chequerwork, with an octagonal turret at each corner.

The building is listed at Grade II* and was conceived as a picturesque architectural feature within the wider designed parkland.

Did you know? Hiorne Tower was not built as a medieval defensive tower. It is an eighteenth-century folly designed to enhance the romantic landscape of Arundel Park.

Swanbourne Lake

East of Hiorne Tower, wooded slopes descend into the valley containing Swanbourne Lake.

Historic England records that the lake was enlarged in 1797 from an earlier mill pond.

Swanbourne Lodge, standing at its eastern end, was built in 1852 to designs by architect William Burn.

The combination of lake, woodland, steep downland and historic buildings creates one of the most picturesque areas around Arundel.

What to Look For in Arundel Park

Feature Why it matters Period / Character
Hiorne Tower Grade II* triangular Gothic folly designed by Francis Hiorne. 1796
Swanbourne Lake Historic lake enlarged from an earlier mill pond. 1797
Beech Woodland Beech formed an important part of the historic planting programme and remains characteristic of the park landscape. 18th century onwards
Flint Park Wall Large parts of the park were enclosed by walls during the late eighteenth and early nineteenth centuries. 1790s–1810s
Open Downland Broad areas of pasture preserve the sweeping scale of the designed landscape. Historic parkland
River Arun Views The eastern escarpment provides views over the flat Arun Valley towards the Downs beyond. Natural landscape

Arundel Park Through the Centuries

Period Development Legacy Today
Medieval Deer parks and estate landscapes connected with Arundel Castle. Historic estate boundaries and landscape continuity.
18th century Creation and major enlargement of the New Park. Large-scale open parkland and designed views.
1790s Planting, enclosure, Hiorne Tower and Swanbourne Lake improvements. Many of the park's defining features.
19th century Further planting, estate buildings and landscape development. Lodges, woodland and mature park character.
20th century Changing estate uses, gallops and storm damage. Mixture of historic and replanted woodland.
Today Historic estate, protected landscape and walking countryside. South Downs scenery and heritage landscape.

Beech Woodland and the Great Storm

Woodland plays a major role in Arundel Park's character. Beech was planted extensively as the park developed during the late eighteenth century.

The Great Storm of 1987 caused severe damage to woodland across southern England, including plantations within Arundel Park.

Many affected areas were subsequently replanted, with beech again forming an important component of the landscape.

Arundel Park and the River Arun

The eastern side of the park drops steeply towards the floodplain of the River Arun.

This contrast between high chalk downland and flat river valley creates some of the best views in the area.

It also explains why the park feels very different from the riverside landscape encountered earlier on walks north from Arundel.

Arundel Park on Our Circular Walk

Arundel Park forms one of the major landscape sections of our Arundel Circular – Castle, River Arun & South Downs walk.

Arundel → River Arun → Burpham → South Downs → Arundel Park → Arundel

After exploring the River Arun and the villages north of Arundel, the route loops back through the historic parkland.

Walkers pass through the landscape associated with Hiorne Tower and Swanbourne Lake before descending towards Arundel.

The final approach offers memorable views of the castle and cathedral above the historic town.

The full circular route is approximately 21 km / 13 miles.

Access note: Arundel Park forms part of a historic estate and not all of the registered landscape is public open-access land. Historic England records the Great or New Park as privately owned. Walkers should remain on public rights of way and other routes where access is permitted.

Walking in Arundel Park

The terrain includes open chalk downland, woodland paths, steep slopes and valleys.

Conditions can become muddy or slippery after rain, particularly beneath trees and on steeper sections. Suitable walking footwear is recommended.

Please stay on public rights of way, respect private estate land, keep dogs under control and follow the Countryside Code.

Walk through Arundel Park with us

Experience Arundel Park, Hiorne Tower, the River Arun and the South Downs as part of our Arundel Circular walk.

View the Arundel Circular – 21 km / 13 miles
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