The caches are located on posting boxes in a few of PE's suburbs. Most are easy roadside caches, but caution must be exercised due to the fact that they are located alongside roads that are frequently busy, with high muggle presence. Each cache container contains a letter of the alphabet; complete the series in sequence and note the letter, to enable you to locate the final mystery cache.
This cache is slightly different to the others in the series; it is a magnetic nano placed a few metres to the north of the actual postbox. The reason for this is the fact that the original containers have disappeared on several occasions, and I suspect that it may be an occupant of one of the nearby residences that has taken offence to the caching activities. No space for trade, BYOP, replace carefully where found.