Have you ever thought about what makes GPS possible?

With the flip of the “Blue Switch,” or Selective Availability, GPS became dramatically more accurate, and a new kind of adventure known as geocaching became possible, turning the whole planet into a playground.

Before Selective Availability was discontinued, the U.S. government made GPS less accurate for everyone except the military, for national security reasons.

On May 2, 2000, the decision was made to discontinue Selective Availability, ending the intentional restriction on civilian GPS accuracy and significantly improving GPS technology for public use. This date is recognized by geocachers as “Blue Switch Day.”

The first geocache was hidden on May 3, 2000, marking the beginning of geocaching—a journey full of innovation and experimentation. Today, there are 3.4 million geocaches in 191 countries.

What better way to celebrate the evolution of geocaching than to represent the butterfly effect, which states that a small, seemingly insignificant action can lead to massive, unexpected consequences over time.

To celebrate this pivotal moment, there are two new souvenirs to earn for Blue Switch Day 2026!

Blue Switch Day 2026 hider:

• To earn this souvenir, geocachers must have a non-Event geocache published between May 1 and 31, 2026.
  • Any non-Event geocache type (excluding Adventure Lab®) counts, as long as it is published between May 1 and May 31.
  • Remember that review times may vary! A geocaching community volunteer will typically begin the review of your geocache within 7 days. We recommend submitting your cache for publication at least a week before the deadline. Learn more about the cache review process in our Help Center.

Blue Switch Day 2026 finder:

• To earn this souvenir, geocachers must find and log one geocache, attend an Event, or complete an Adventure Lab® Location between May 1 and 3, 2026.

How will you celebrate Blue Switch Day this year?