A little-known stone structure in northwest England has been added to the country’s list of protected heritage sites, after officials granted it Grade II* status following an assessment of its architectural and historical significance.

The building, known locally as Henry’s Castle, is located in the Lake District and had most recently been used as a shelter for livestock.The designation was approved by the Department for Culture, Media and Sport on the advice of Historic England.

Grade II* status is awarded to structures deemed of “more than special interest” and accounts for approximately 5.8% of all listed buildings in England, placing Henry’s Castle among a relatively small group of protected sites.The listing brings the structure into the same category as prominent landmarks such as Battersea Power Station, Transporter Bridge, and the London Coliseum.

Despite this classification, Henry’s Castle differs significantly in scale and visibility, consisting of a limestone rubble building situated on elevated ground near Kendal, within walking distance of the village of Underbarrow.According to Historic England, research indicates that the structure may date back to the 14th century and exhibits characteristics associated with high-status construction.

However, its original function remains unclear. While it has been used in more recent centuries as a field barn, experts suggest that this was not its initial purpose.Sarah Charlesworth, a listing team leader at Historic England, said the building’s ambiguity contributes to its significance, describing it as an example of a rare structure that continues to prompt unresolved questions about its origins and use.

The building first drew renewed attention during a 2022 site visit by Rose Lord, a built environment adviser with the Lake District National Park Authority. Lord noted that, despite its degraded condition and evidence of long-term agricultural use, several architectural features indicated a more complex history.

She identified elements including a corbelled chimneystack and a corbelled garderobe, features not typically associated with simple agricultural buildings.Interior observations also pointed to earlier domestic or high-status use.

The presence of plastered and limewashed walls, combined with evidence of internal fireplaces and a structured arrangement of openings, suggested a level of design and occupation inconsistent with a standard barn.

Subsequent conservation work, carried out over four years by archaeologists, architects and engineers, focused on stabilising and restoring the structure. Particular attention was given to the roof, which includes an oak truss system described as precisely finished and consistent with high-quality carpentry from the late medieval period.

The craftsmanship of this central truss has been identified as one of the building’s most significant features.Various interpretations of the building’s original function have been proposed, though none have been conclusively established.

Suggestions include its use as a lookout or defensive dwelling, a hunting lodge associated with a deer park, or a seasonal residence of relatively high status. Historic England has also noted similarities with bastles, a type of fortified farmhouse found in the Anglo-Scottish border region and designed to protect inhabitants and livestock from raids.

However, the structure’s location south of the traditional bastle distribution area makes a direct classification unlikely.Historical records indicate that the building underwent changes in use over time. It is believed to have been adapted for domestic occupation during the 16th or 17th century, before being repurposed as a field barn by the 19th century.

Its current name derives from Henry Willison, a former owner.Officials involved in the conservation project described the Grade II* listing as a significant outcome, particularly given that most structures of comparable importance have already been identified in earlier heritage surveys.

The designation ensures legal protection and formal recognition of the site’s architectural and historical value.As part of ongoing efforts to manage and interpret the site, authorities plan to install informational panels outlining current research and findings.

Additional measures include the placement of a nesting box intended to support local owl populations, reflecting an effort to integrate conservation of both built and natural heritage.

The listing of Henry’s Castle highlights the continued identification of historically significant structures within rural landscapes and underscores the role of ongoing research and fieldwork in reassessing buildings that may have been overlooked in previous surveys.