The ruins are a set of large standing stones located in The Lost Grove, to the east of the central crater. Interacting with it replays a memory of the interaction between Solak and Serenist elves named Merethiel, Eredthor, Saeldor and Faerdhinen who were sent to aid him.
Using the 'Reminisce' option will prompt the dialogue and also unlock the Memories From The Grove music track.
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