Geocache / Letterbox

Geocaching is a high tech “treasure hunting” game played throughout the world by adventure seekers equipped with GPS devices or smart phones.  The general idea is to locate hidden containers called geocaches or simply caches. Once you find it, take a trinket and leave one of your own behind, sign the logbook and share your experiences through

Geocaching on McHenry County Conservation District property - due to the similarity, all rules apply to Letterboxing as well:
  • Follow all District rules and regulations - all geocaches are required to be 12 feet or less from a designated trail.  You may leave the trail for the cache as long as you are within the 12' 
  • Geocaches may not be affixed to any natural or man-made structure with the exception of magnetic caches.  Magnetic caches cannot be placed on any electrical boxes, pipes or other mechanical structures.
  • Light pole caches ("lpc") are not allowed
  • Certain areas may be closed to geocaching for a variety of reasons
  • Permission must be obtained prior to placing a cache
Complete list of geocaching /letterboxing rules.

Cache Your Way 2022

otter coin

Each year the District puts together a Cache Your Way Challenge.  The 2022 Cache Your Way season will be July 31st-November 30th. This year’s theme will be in recognition of the river otter returning to the Nippersink Creek in Glacial Park. Complete the sheet and earn the special coin by completing all of the caches for this year. There are a limited number of coins—first-come, first-served; 1 coin per household. All caches will be live on Note: This is a separate series from the GeoSeries. 

Find us on Facebook Cache Your Way Across McHenry County Group

Still working on the 2021 series and need a passport? Find it here. 

Cache Your Way Across McHenry County Ongoing GeoSeries
The District also maintains an ongoing GeoSeries, Cache Your Way Across McHenry County, highlighting the BEST spots throughout the McHenry County Conservation District.  A GeoCoin is available for the completion of this program as well. To participate in our program and earn a special District geo-coin, follow these simple steps:

1.) Download a McHenry Conservation District Cache Your Way Across McHenry County  GeoSeries Passport
***Passport updated 6/1/2020 due to one cache temp unavailable
2.) Go to and create a login – it’s free for basic membership!
3.) Start your search and locate a cache using a hand-held GPS unit or a GPS app on your smartphone. Our containers are clear plastic containers and will have official District labels and info cards.
4.) When you find a cache, log your name on the logbook inside. Write the answer to the question in your passport. (Information and your question is located on the cache’s page on Exceptions are the Earthcaches: there are no log books or containers at Earthcaches – and the two smaller-sized caches.
***If you have already found the 4 pre-existing Earthcaches you do not need to find them again! If you remember the answers, use those. If you do not, simply put the date and your geocaching ID down for staff to check the logs to see your recorded visit.***
5.) Some of the caches may have travel bugs. Please move these bugs along and do not keep them! You will get your own to keep when you finish the program.

Claiming Coins
Complete all the caches in the series and do one of the following:

A. Bring your passport to one of our facilities (Prairieview Education Center or Lost Valley Visitor Center). Be sure to check each facility’s hours before heading out. Hours and days open vary depending on the site.
B. Mail the passport to: McHenry County Conservation District, Attn: GeoSeries, 18410 US Highway 14, Woodstock, IL 60098
C. E-mail a copy of the passport to

***Note on site closures or temporarily disabled caches***
If you are traveling from out of town and a cache is temporarily disabled either due to a site closure or some kind of issue with the cache, on the passport record disabled and the date. You will still be able to claim a coin!