(Image: NASA, public domain)

Welcome to the twentieth installment of this edition of our weekly link round-up, delivering the best links from our friends, partners and those we admire.  Enjoy!

The Awesome Graffiti of Belgium’s Doomed Ghost Town (Environmental Graffiti)

The Only American Not on Earth on September 11 (Twisted Sifter)

Inside Auschwitz: Haunting Mementos of the Nazis’ Largest Death Camp (Environmental Graffiti)

Ghost Architecture: Building Demolition Photo Composites (WebUrbanist)

San Francisco Past & Present: Blended Images from 1906 and 2o12 (WebUrbanist)

Crumbling and Abandoned (Marianas Variety)

Renoir Masterpiece Discovered in £5 Box of Trinkets (The Telegraph)

Gates Factory: Urban Explorers Still Eager to Prowl Abandoned Plant (Westword)