This is one more amazing find of the car boot sale. It is a postcard of Big Torii Itsukushima Aki in Japan. You can see a modern postcard of this shrine and some more information here.
On the back of the postcard there is a stamp of Nagasaki and the date 26 November 1925.
In Japan, official postcards were introduced in December 1873, shortly after stamps were introduced to Japan. Return postcards were introduced in 1885, sealed postcards in 1900, and private postcards were allowed from 1900.