QUINTESSENTIALLY English red pillar boxes, of which there is at least one fine example in Swindon, are to continue to be a distinctive feature of our streets.

English Heritage has teamed up with Royal Mail in a promise to preserve all 85,000 of the country's remaining boxes, describing them as national icons.

It should ensure the longevity of Swindon's red post boxes, such as the Victorian example in Fleet Street.

"They are wonderful things and properly regarded with great affection," said English Heritage's chief executive Sir Neil Cossons. "They have every quality of good design."

The move coincides with Royal Mail's unveiling of a set of stamps to celebrate 150 years of the letter box.

The boxes were the brainchild of novelist Anthony Trollope who, 150 years ago, was a General Post Office employee who was sent to the Channel Islands to report on ways of improving the postal service.

The first public pillar boxes were not red but green and were trialled in St Helier, Jersey, on November 23, 1852.

Instantly popular, within 10 years they were being installed all over Britain and their red colour was introduced in 1874 to make them clearly visible.

Listed examples include rare octagonal and fluted designs and some from the 1930s, including one outside Windsor Castle, were painted air force blue and designed for air mail.