The National Trust for Places of Historic Interest or Natural Beauty (informally known as the National Trust) owns or manages a range of properties in the ceremonial county of Somerset, England. These range from sites of Iron and Bronze Age occupations including Brean Down, Cadbury Camp and Cheddar Gorge to Elizabethan and Victorian era mansions, which include examples such as Montacute House and Tyntesfield. Some of the smaller properties include Coleridge Cottage and Stembridge Mill, the last remaining thatched windmill in England.
The ceremonial county of Somerset is governed by three unitary authorities, North Somerset, Bath and North East Somerset and Somerset Council.
Many of the buildings included in the list are listed buildings or scheduled monuments. Listed status refers to a building or other structure officially designated as being of special architectural, historical, or cultural significance; Grade I structures are those considered to be "buildings of exceptional interest". Listing was begun by a provision in the Town and Country Planning Act 1947. A scheduled monument is a "nationally important" archaeological site or historic building, given protection against unauthorised change. Scheduled Monuments are specified in the Ancient Monuments and Archaeological Areas Act 1979, which defines a monument as: