The tourney at Harrenhal
The greatest tourney in living memory, at the cursed castle, attended by nearly everyone whose choices would matter. Rhaegar Targaryen won it ÔÇö and then rode past his own wife to lay the crown of winter roses in the lap of Lyanna Stark, who was betrothed to Robert Baratheon. Men who were there say the silence lasted a very long time.
The fuller tale
The tourney at Harrenhal in 281 was the largest in living memory and nearly everyone whose choices were about to matter was there. Lord Whent's stated reason was his daughter's name day; the purse was enormous and the timing was odd, and it has been suggested ever since that the whole thing was arranged so that the lords of the realm could be got into one place to discuss what to do about the king. If so, nothing came of it, because the king turned up.
A mystery knight rode in the lists with a laughing weirwood on his shield, beat three knights whose squires had mocked a crannogman, took their ransoms in apologies, and vanished. Aerys was convinced it was an enemy and sent his son to find him. His son came back with the shield and no knight.
Rhaegar Targaryen won the tourney. Then he rode past his own wife, who was sitting in the stands, and laid the crown of blue winter roses in the lap of Lyanna Stark, who was sixteen and betrothed to Robert Baratheon. The histories are unanimous that nobody said anything, and that the silence went on for a very long time.
Everything at once
Ned Stark was there, and his brother Brandon, and his sister. Robert Baratheon was there. Jaime Lannister was named to the Kingsguard there, which took him out of the line of Casterly Rock and enraged his father into resigning as Hand. Howland Reed was there. Ashara Dayne was there. Barristan Selmy won a joust and Rhaegar beat him.
Everyone who breaks the realm in the next two years is in the same field for a fortnight, and the last thing that happens is a married prince crowning another man's betrothed in front of all of them.
Elsewhere in the wiki
 See the world as it stood in 281 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.