Letterboxing started a LONG time before geocaching - try 1853! Modern letterboxers look for containers that are very similar to geocaches, using clues to find them instead of coordinates. The other big difference is they contain a rubber stamp. Letterboxers carry their OWN rubber stamp and their own logbook, and make an impression of their stamp in the box's logbook, and then use the stamp in the box to make an impression in their logbook.
Letterbox hybrids can be treated as a normal geocache, found using the coords, and can be signed inside with your geoname. Or you can bring a stamp and use the following clues to find the cache.
If you want to use the clues:
Enter Craighead Forest Park and look for a memorial with a statue to your left. Circle the flower garden and pull up by the memorial. This memorial is for children who have died young. Feel free to take a few moments and honor them and their parents who lost them. When you are ready, stand in front of the statue. The statue is holding a winged creature to one side. Turn and face the opposite side. Do you see something growing nearby that has a strong relationship with the number "four?" Go look at the base of where that is growing and you will find the box.
This cache contains a rubber stamp along with some swag. Feel free to exchange swag as usual, but do not take the stamp and inkpad please!