Cache is NOT at posted coordinates.
This is the bonus cache for the Historical Dundas Adventure Lab. Complete each stage of the adventure lab to get the numbers needed to find the cache.
Also, three of the stages will have a hint for this bonus cache.
N43 16.ABC W79 57.DEF
https://labs.geocaching.com/goto/DundasAL
Zntargvp xrl obk.
Zber uvagf va gur nqiragher yno.