Original features

Horace Walpole - son of Britain's first Prime Minister, Sir Robert Walpole - bought a modest cottage in Strawberry Hill, Twickenham, in 1747. He doubled its size, added towers and battlements, and transformed it into "a little Gothic castle". He also used it as a setting for his pioneering Gothic novel, The Castle of Otranto (1764).

Widely regarded as the UK's finest example of the Georgian Gothic Revival style, it is a Grade I listed building. It appeared in the 2004 World Monuments Fund list of the 100 most endangered world heritage sites.

The original edifice was significantly modified in the 19th century by Frances, Countess Waldegrave, the daughter of a Jewish opera star who married into the Walpole dynasty. She added an extra wing to link its villa and the adjacent office block.

The property was purchased by what is now St Mary's University College in the 1920s. Although the Strawberry Hill Trust was established in 2002 to restore "Walpole House" and open it to the public, the elegant Waldegrave rooms - the dining room, billiard room and drawing room, with an anteroom leading to the grounds via an ornate iron staircase - still form part of St Mary's and are often used for its social events.

Send suggestions for this architectural series to: matthew.reisz@tsleducation.com.