Objective Landscape characterisation aims at categorizing and describing areas with similar patterns of element combination, simplifying infinite landscape complexity into manageable spatial units. Existing relevant literature tends to explore concepts and frameworks applicable to all landscapes, focusing on how to enhance process transparency and incorporating historical complexity within universal technical routes, and has yet to be differentiated according to different landform types. This paper seeks to clarify whether mountain landscape characterisation different from that of lowlands and identify ways of interpreting the complexity of cultural landscapes in mountainous areas. The findings will contribute to a deeper understanding of the complex relationships between natural and cultural elements in mountain cultural landscapes, as well as to a more targeted approach to future management.

Methods This study focuses on collecting documents related to landscape characterization of 15 national parks, including 20 landscape character assessments (LCA), 10 historic landscape characterisations (HLC), and 2 historic land-use assessments (HLA). For the LCA documents, this study adopts a content analysis method to categorizing and analyzing recurring the type and frequency based on NVivo software. Two coding approaches are adopted and integrated. This study also analyzes the treatment of historical complexity in the LCA documents of the national parks with reference to the relevant HLC and HLA documents, but without coding due to the lack of a consistent assessment methodology across U.K. in this aspect.

Results In terms of landscape change, a total of 41 factors were identified in the relevant LCAs, which can be grouped into 3 broad categories, including natural influence, cultural influence, and force for change. A total of 21 mapping attribute related factors were identified and grouped into 3 categories, including natural attribute, cultural attribute, and perceptual and aesthetic attribute. The compound names of landscape character types are broken down into a series of words, which are grouped into 24 factors that fall into 3 categories, including as natural character, cultural character, and perceptual and aesthetic character. As far as the treatment of historical complexity is concerned, although all U.K. National Parks LCAs describe landscape changes according to historical phasing, they mainly use natural attributes, current land use and field morphology as the criteria for landscape character categorization, and they seldom include temporal information in the naming of landscape character types. Only a few LCAs incorporate historical information into landscape character classification, such as the Wales LCAs. To compensate for the disadvantage of over-simplifying the temporal depth of LCA, many national parks in England and Scotland create separate HLCs or HLAs, led by archaeologists and historians.

Conclusion This study reveals variations between mountain and lowland national parks. The approach to historical complexity in different national parks is primarily influenced by the administrative system of the region in which they are located, rather than the type of park. Natural topographic conditions can have a significant impact on landscape character assessment, even though similar research frameworks and technical routes may be used for landscape character assessment in mountains and lowlands.

Conclusion The findings enhance understanding of UK National Park assessment models, they also offer insights for characterizing cultural landscapes in mountainous national parks globally. The study provides a foundation for future research to comprehensively interpret the landscape characterisation models in UK national parks and guide similar regions with mountainous landscapes.