According to what horological system are years marked (like our "AD" and "BC")?
In addition, what is the current year on their calendar (assuming a canonical calendar exists)?
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Sign up to join this communityAccording to what horological system are years marked (like our "AD" and "BC")?
In addition, what is the current year on their calendar (assuming a canonical calendar exists)?
The Points of Light campaign setting (in which Nentir Vale exists) does not have a canonical calendar system established.
Some of the rulebooks refer to things happening in the past, and so the fan community has started using 'CY' as a short hand for 'Current Year.' So something that happened 300 years ago would be written as "CY-300"
But, very much unlike the Forgotten Realms campaign setting which has multiple calendar and dating systems established, no such system is established for the 4E Points of Light setting. In fact, much of the Nentir Vale setting is intentionally left vague in its details to allow DMs as much leeway as possible in determining what has happened and when. When this setting speaks of events of the past, they simply use 'Centuries' or 'Millennia' or Decades' in place of actual dates.
I have seen two dating systems primarily used, but these are fan-created.
You have NF, which stands for Nerath Founding...and measures years since the Nerath Empire was founded. From Dragon Magazine 393, we know that Nerath was founded about 600 years ago and is marked by when the Flame Imperishable was first lit, which would put the current date somewhere around NF600.
The other I've seen is AE, which stands for After Empire. Nerath fell to the gnolls about a hundred years ago, which would put the current date as somewhere around AE100 or so.
Again, those two options are simply the two most common fan-calendars I've seen in use. There is not an official calendar or year model released by Wizards for the Nentir Vale.