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Events on Wednesday 6 May 1840 1
1840Penny Black postage stamp enters useFirst adhesive postage stamp in the worldThe Penny Black, the world's first adhesive postage stamp, went on sale on 1 May 1840 and became valid for use on 6 May 1840 across the United Kingdom. It featured a profile of Queen Victoria and was part of postal reforms led by Rowland Hill. The stamp established the prepaid postage model still used worldwide.