Nice idea. Read the small print.

Dear Photograph is a site that invites people to post pictures that incorporate photographs from their past taken in thelocations featured in the original picture.  It’s worth a look.

Also worth reading the site’s small-print before you submit anything;

“When you submit your materials, you grant dearphotograph.com a non-exclusive, irrevocable, royalty-free license to use the work to be used, copied, sub-licensed, adapted, transmitted, distributed, published, displayed or otherwise under our discretion in any and all media.  All rights owned and controlled bydearphotograph.com”.