A stamp's journey can provide me with hours of fascination. Let's explore the two key markings that document this journey, from the various types of postmarks and cancels to the ways in which I research and learn from them.

Learn about the sponsor: https://stamps.org/
Video about Pen Cancels:    • What's the deal with Pen Cancels?!  
Site for uploading and examining postmarks/old documents: http://retroreveal.org/