Almost every zone in ESO has a Public Dungeon in which you will find one skyshard, a group event and several boss's.
The group event is the skull marked in red and on completion (only first time) you will gain a skill point. There are also more than one boss and you will get an achievement for killing some of them and one achievement when you have killed all.

This guide provides a map of all large public dungeons in ESO, marked with group challenge, champion and skyshard locations. Sorted in order of zone's and faction.

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