Using This Site

How to Use the Search Function:

Entries into the search box will search all text associated with the photo pairs.  This includes the change descriptions, locations, photographer names, photo collections, notes, and years.  Type the word you are looking for using the following tips:

  • “Glacier” will return all photo pairs with “Glacier” or “Glaciers.”
  • “Visitor center” will return all photo pairs with either the word “Visitor” or “center” in any order.
  • “Visitor+center” will return only photo pairs with the phrase “Visitor center.”
  • Capital letters do not matter.
  • Partial words will be taken as such, and will return photo pairs that use whole words containing those letters.

Additional Features:

As you browse through the photo pairs, be on the lookout for icons that reveal hidden content.

The “play” icon will open a new window with an animation of the current photo pair.  Animations were made by digitally aligning the photo pairs and fading one into the other.  When viewing animations, one can witness decades of change occur in just a few seconds.  However, keep in mind that intermediary stages are not shown.  Animations are good for highlighting especially drastic changes.

The pencil icon will add annotations to the current photo pair.  Annotation marks (i.e. letters, lines, or arrows) are sometimes used in the change description to help direct you to important features.  They always will help you align particular features in the photo pairs, so the letter “a” on the first photo pair will be in the same place on the second photo pair.  Sometimes changes over the intervening period are so great that annotations are necessary!