A Vincent Van Gogh painting of a Paris street has gone on display for the first time after spending more than 100 years behind closed doors.
A Street Scene In Montmartre has been owned by a French family for most of the time since it was painted in 1887.
Sotheby's estimates it could fetch up to eight million euros (£6.9m) when it is sold at auction next month.
Van Gogh expert Martin Bailey told BBC News that this is "the first time we are able to see it properly".
Small reproductions have been made in the past, often in black-and-white. "What is exciting is that it is a Van Gogh painting which has been hidden away ever since it came off the artist's easel," Mr Bailey said.
"It has always been in private collections, so only the owners and their friends knew it.
"It is an interesting picture because it is a transitional work between Van Gogh's Dutch years, when he painted in dark, earthy colours, and the exuberant works that he did in Provence. It was in Paris that he discovered the Impressionists, and this led him to explore colour."
It is one of a series of works Van Gogh created while lodging with his brother Theo in 1886 and 1887 a short distance from the street depicted in the painting.
The estimated price tag of five to eight million euros reflects the fact that the artist's Paris paintings do not fetch the "mega sums" of his Provence paintings, added Mr Bailey, who writes a blog on Van Gogh for The Art Newspaper.
"But until the hammer goes down, one obviously never knows what will happen at an auction. There is now a great deal of interest in Van Gogh in the Far East, so the Van Gogh market is truly global."
The painting will be displayed at Sotheby's auction houses in Paris, Amsterdam and Hong Kong ahead of its sale on 25 March.
Sotheby's said: "The appearance on the market of a work of this calibre, and from such an iconic series, is undoubtedly a major event."
Montmartre was still semi-rural when the scene was painted. A windmill features prominently behind some perambulating locals. The famous Sacré-Cœur church that now dominates the area was under construction at the time.
Van Gogh left Paris for the south of France in 1888. He died near Paris in July 1890.