I owe this one to Two_Point's story, The Forgotten Tree. You don't have to read it to make sense of this, but I did want to acknowledge her influence and thank her.
White towers glistened in the sun, echoing the glorious snows of the surrounding mountains and the luscious green of the plain. Small, but detailed, a great eagle soared over the highest peaks of the Echoriath, and for a moment, just one absolutely perfect moment, Erestor was back in Gondolin. Air, crisp and clear, touched his cheeks, and nearby he heard the bush of an eagle's wing, heard the chiming of bells and knew who it was who rode towards him. Memory merged with reality ....
...and brought him crashing back to the now. Opening his eyes, Erestor beheld the concerned face of his lord.
Not Turgon, though there was something of that long-lost king's wisdom in the storm-grey eyes. Without thinking he reached forward to cup that face, grounding himself once again. Time was a querulous creature, memory could be fickle; touch did not lie.
"Erestor." Softly, and Elrond reached to echo Erestor's touch, wiping a tear away with a gentle hand. A healer's hand.
No questions. Elrond knew that sometimes the ancient elves needed a moment to come back from the long paths of memory. A smile touched his mouth, graced grey eyes.
A nod and the hand fell away, granting Erestor his dignity, his pride.
Erestor licked his lips, tasting salt and wondered at himself. Tears? After all this time. Ah, the heart was unknowable, so many joys and sorrows making their home there. He nodded, though for himself or his lord, Erestor could not say. "I did not realize the mural was finished."
One swift glance, encompassing empathy and understanding, Elrond too knew what it was to lose those things beloved, and the grey gaze turned to the wall. "Lindir played as they painted, you know. Old songs, songs he said he had learned from you."
The wonder of elven creation, and the ache it left one with, was the gift of imbuing whatever it was created with a bit of memory and emotion. Cloaks could hide the wearer if that thought was woven into the fabric. Hair could be woven to wondrous wings, though that art was lost with the sinking of Beleriand. Paintings could hold more than mere sight would tell....
"His curiousity is insatiable." Husky, quiet, he let his gaze follow an eagle, but remained when he was, where he was.
Another time, he would come back and wander the painting as he once had Gondolin's winding streets.
Elrond only gave a nod and turned, looking back to offer a sweet smile that echoed one long ago of a child who had taken Erestor's hand as they walked a narrow mountain path. "When you are finished, come and find me and we will dine together if you wish."
"I would like that, milord." A bow of his head, raven's-wing black hair sweeping forward, and Erestor watched his lord walk away, leaving him to his contemplation.
Just one thing and he would go; the painting would be there for ages. He had time, nothing but time. His gaze followed a road, up, up, around a bend and to the wall where fountains had sung night and day.
His home. Erestor touched the spot gently and closed his eyes for a moment, offering a silent prayer to the Powers for those of his House.
For Adar. Naneth.
As if they knew the path as well as his feet, long tapered fingers traced a way southward, past the King's Square and there.... There was the other home. One also familiar. Beloved.
Golden light swept over Erestor as the sun headed for the far end of the valley, washing Imladris in its warmth and beauty.
Peace, he whispered in his mind, not knowing if the other would, or could hear. Did death break bonds, untangle fëar and leave both bereft?
Somewhere a bell rang and elves began to sing a paean to Elentári.
Deep breath, memories saved for another time, beloved, cherished as those letters tucked away in the box with the rayed sun, and Erestor walked away from the mural, softly joining in the Song.