The container IS at the posted coordinates. The puzzle IS the container. The 'challenge' IS the puzzle. [This IS not a hint.]
PLEASE be gentle and patient, and careful not to bend, break, or lose anything.
Please also be aware that there is barbed wire, which will only be an issue if you drop anything. You can do this alone, but a partner would be more fun and helpful.
Please also park completely off the road. Some vehicles coming and going from the park OR the boat ramp are quite large and wide.