• A new exhibition featuring some of London’s leading ladies of the eighteenth century opens at the National Portrait Gallery today. The First Actresses: Nell Gwyn to Sarah Siddons is the first exhibition devoted to eighteenth century actresses and features 53 portraits depicting the likes of Gwyn and Siddons as well as Lavinia Fenton, Mary Robinson and Dorothy Jordan. Highlights of the exhibition include a little known version of Joshua Reynolds’ portrait of Sarah Siddons as the “tragic muse”, William Hogarth’s The Beggar’s Opera and Thomas Gainsborough’s portraits of Giovanna Bacelli and Elizabeth Linley. The exhibition reveals the key role these women played in the celebrity culture found in London (and elsewhere) during the period. As a counterpoint, an accompanying exhibition displays photographs and paintings of some of today’s actresses. Runs until 8th January (an admission charge applies). For more information on the exhibition or the programme of accompanying events, see www.npg.org.uk.

• Cemetery in Hackney and Kensal Green, a park in Hounslow and a Piccadilly property formerly used as the Naval and Military Club are among the “priority sites” listed on English Heritage’s annual Heritage At Risk Register. Released earlier this week, the register’s 10 London”risk priority sites” include London’s first metropolitan cemetery – Kensal Green (All Souls) – which dates from 1833, Gunnersbury Park in West London – featuring a large country home known as Gunnersbury Park House, it was built in 1801-28 and later remodelled, and a mansion at 94 Piccadilly – built in 1756-60 for Lord Egremont, it was later used at the Military and Naval Club and is now for sale. Others on the list include Abney Park Cemetery in Hackney – laid out in 1840, it is described as London’s most important Nonconformist cemetery, a medieval manor farm barn in Harmondsworth in London’s outer west, Tide Mill in Newham, East London, and the entire Whitechapel High Street and Stepney Green conservation areas. For more information, see www.english-heritage.org.uk/caring/heritage-at-risk/.

• On Now: The Heart of the Great Alone: Scott, Shackleton and Antarctic Photography. Opening at the Queen’s Gallery, Buckingham Palace, tomorrow, the exhibition marks the centenary of Captain Robert Scott’s ill-fated expedition to the South Pole and features a collection of photographs presented to King George V by the official photographers on Scott’s expedition of 1910-13 and Ernest Shackleton’s expedition of 1914-16 as well as unique artifacts including the flag given to Scott by Queen Alexandra (the widow of King Edward VII) which was taken to the Pole. Highlights include Herbert Ponting’s images The ramparts of Mount Erebus and The freezing of the sea and Frank Hurley’s stunning images of Shackleton’s ship Endurance as it was crushed by ice. Runs until 15th April, 2012 (admission charge applied). For more, see www.royalcollection.org.uk.