Note: Bring a pen and paper to solve this little mathematical challenge!
There are sections of the Bruce Trail that detour along km stretches of road or go through Provincial Parks where no caches are allowed. For these sections, we've set up "Bi-Directional Multi-Caches." These are specifically designed for hikers with the intent that they don't have to double back at any point. To accomplish this, we've set up two multi-caches which have puzzles to solve their opposite. Since these multi-caches solve each other, we can't post the starting co-ordinates. Instead, we have placed the starting co-ordinates in the nearest traditional cache.
When visiting the north or south bound traditional cache, taped to the lid you will find the co-ordinates to the final stage of the closest multi. (Remember, the start location of the south bound multi, is the same as the final for the north bound. This allows you to log both multi-caches while still walking only one direction.) Once you arrive at the co-ordinates that were taped to the lid of the original traditional cache, you will find a puzzle to complete the second multi of the bi-directional set.
Since both finals are in the traditional caches at either end, we realize that you could potentially cheat and that's okay too if you're a car person!