Robert takes the throne, and a Stark rides south
Robert Baratheon is crowned; Ned Stark rides on to the Dornish marches to find his sister, and comes home with her bones, a silence he keeps for fifteen years, and a boy he calls his bastard. The realm settles into seventeen years of an uneasy peace, held together by a Hand named Jon Arryn and by everyone agreeing not to say certain things out loud.
The fuller tale
Robert Baratheon was crowned in a city that still smelled of smoke. Ned Stark did not stay for it. He rode south to the Dornish marches with six companions to find his sister, and at a tower in the Red Mountains he found three of the Kingsguard instead ÔÇö Ser Arthur Dayne, Ser Oswell Whent and Ser Gerold Hightower ÔÇö who had not been at the Trident, had not been at the sack, and were still standing where they had been told to stand.
Seven men rode up to that tower. Two rode away. Ned came home with his sister's bones, a promise nobody else heard, a sword returned to Starfall, and a newborn he called his bastard and would not discuss with anyone, including his wife.
The realm settled into seventeen years of peace, which held because Jon Arryn was an extremely capable Hand and because a great many people agreed not to say certain things out loud. Robert hunted, drank, and spent money he did not have. Tywin Lannister's daughter was married to him. Two Targaryen children got out to the Free Cities. Nothing was resolved; it was postponed.
The question the tower asks
Three of the finest knights in the world stayed at a tower in the desert while their king was killed and their city sacked. Whatever they were guarding, they thought it outranked both. Ned Stark never told anyone what he found, and the one man alive who was there with him spent the rest of his life in a swamp, saying nothing.
Everything hidden in that silence surfaces at the very end of this chronicle, and by then it is far too late for it to save anyone.
Elsewhere in the wiki
 See the world as it stood in 283 AC What became of it  if an ending is written, it is here. Spoilers.
The chronicle records no ending here ÔÇö or none the maesters have set down.