Art fans in Vermeer ticket rush

They have been queuing around the block for tickets - and they will continue to do so every day until the biggest, and never to be repeated, exhibition of the works of the 17th century Dutch master Johannes Vermeer closes on 16 September.

And while visitor numbers will not rival the British record 813,000 for Monet in the 20th Century at the Royal Academy in 1998, the National Gallery knows it is setting the pace for the London summer art season with this exhibition.

Before it opened its doors this week 18,000 advance tickets at £8 each had been sold here and around the world. Earlier this year the same exhibition drew 545,000 people to New York's Metropolitan Museum of Art.

But the National has taken the view that Vermeer's closely-observed domestic scenes of stunning clarity and quality need quiet study and it has capped the number of visitors to 3,000 a day. This means - despite keeping its doors open late until 9pm on Saturday and Sunday evenings - a total of 270,000 will have viewed Vermeer and The Delft School by the time it ends.

The National knows it will sell every ticket it has printed - and could sell them twice over - but 270,000 will still represent the third most successful exhibition in the gallery's history.

It is the largest showing of work by the artist - who because of the obscurity of his life became known as The Sphinx of Delft - ever to be displayed in the UK. The previous largest was at the Royal Academy in 1921. After the exhibition closes, the 13 Vermeers on show in seven rooms will be returned to the museums and private collectors who loaned them and are unlikely to be seen together again. The Vermeers include Allegory of the Faith, Allegory of Painting, Head of a Young Girl, The Girl in a Red Hat, Young Woman Reading a Letter (aka Woman in Blue) and The Milkmaid.

They are complemented by almost 50 works by other artists of the Delft school which flourished in the late 1640s, including 11 by Pieter de Hooch.

There are only 35 known Vermeers in the world and perhaps his most famous work - View of Delft, executed around 1660 - now hangs in the Mauritshuis in The Hague.

Johannes Vermeer (1632-1675) was born the son of an innkeeper in Delft and spent his entire career in the city. At 21 he married Catharina and enrolled in the artists' guild.

In his own lifetime his works were regarded as experimental and not widely appreciated, and it is thought he struggled to make a living from his sideline as a part-time art dealer. He also struggled to feed his family of 15 children and many of his own paintings were given to bakers, grocers and other tradesmen in lieu of the money owed. He was declared bankrupt at the time of his death, aged 43, from unknown causes.