Official details are below.
Descend into DARK SOULS™ III: The Ringed City™, the second and final DLC expansion for DARK SOULS III, available digitally on March 27, 2017 for STEAM™ and March 28, 2017 for the PlayStation®4 computer entertainment system and Xbox One.
The new DARK SOULS III: The Ringed City trailer and screen shots highlight the decrepit Ringed City along with the lost wanderers, royal residents, and fearsome beasts that are found within its walls.
The new trailer can be found with the following YouTube link: https://youtu.be/5VhnJ-7PbTE