In the past posters were used for various purposes. They were designed by various artists, but also in different editions. Posters were basically seen as a disposable product, which meant that the way they were hung up was detrimental to the paper. They were hung by glue, thumbtacks or tape. When people got tired of the poster or when the poster had achieved its goal, it was usually thrown away.
Posters, especially old ones in good condition are extremely rare. Posters can be restored, but this is work for a specialist. Litho Art tries to save posters from their demise and treat them with value and give them a new home. We like to sell the poster "pure" if that's possible. That means that we try to prevent restoring the poster if that's possible. This is because the more original the better. Sometimes we can't prevent this so a poster has an restoration already or needs to have one.