Fans of The Lord of the Rings get really invested in the characters, particularly those main ones who were a part of the Fellowship of the Ring. These characters are rich enough that a lot of people are still interested in where their journeys take them even after they have completed their main goal within the story. One of the characters who is most central to the action in LOTR is the wizard Gandalf, who accompanies the heroes on their quest and is an integral part of Middle-earth itself. He - as well as the iconography around him thanks to the film adaptations - is one of the most recognizable and well-known characters from the series, but his story doesn't end after the main action is over.
As one of the Maiar, Gandalf lived for a very long time before the events of the story, so it's only fitting that his journey extends past where things end in The Return of the King. While his life post-war was not as long as all that came before it, he still managed to be incredibly influential, as always, and continued to affect the world. But what exactly did he get up to once the Ring was destroyed and everyone (presumably) went back home to have a much-deserved rest? Where did Middle-earth's favorite wizard find himself next?
How Did LOTR End?
The end of the main conflict in The Lord of the Rings comes when the One Ring is finally destroyed in the fires of Mount Doom, thereby defeating Sauron, the big bad of Middle-earth. Frodo completed his mission of delivering the Ring to Mordor, though he had trouble ridding himself of it in the end. The Ring only fell into the fires when Gollum tried to take it back from the Hobbit and the two desperately fought over it, leading to Gollum falling from the ledge with the Ring (still attached to part of Frodo's finger) into the lava below. This triggered the fall of Sauron, destroying Mordor and ending the war, marking the end of a long struggle for the people of the land against the dark forces. Aragorn became the King of Gondor, restoring peace to the kingdom that had been struggling either without a ruler or with a bad one for a long time.
The remaining Orcs of Mordor were eventually wiped out in a campaign to bring further peace to Middle-earth. The Hobbits went back to the Shire, only to find it in ruins because of Saruman's influence (in a sequence that was cut from the film adaptations), and they had to complete one last battle in order to win it back and save their own people. Frodo eventually found that he couldn't readjust to normal life, and instead chose to accompany the Elves to the Undying Lands, which was a very high honor to be offered in the first place. The other characters went on with their lives as well, becoming great military heroes, nobility, or even just family men. But what happened to their wizard friend once the main story was over?
Where Did Gandalf Go After The War of the One Ring?
Though many took it upon themselves to rebuild Middle-earth after the war, Gandalf decided to give himself some time to rest. With the defeat of Sauron, he knew that his purpose on Middle-earth was complete, and there was nothing more left for him to do. He didn't get involved in the Scouring of the Shire, knowing that the Hobbits could take care of it themselves. He was present at Aragorn's coronation and even presented him with his crown, but that was essentially his last official act as a being of great importance within Middle-earth.
He had a long talk with Tom Bombadil that seemingly lasted for many years. Tom Bombadil is one of the stranger Tolkien characters (and another omission from the films), as he is an incredibly powerful being, though the true nature of who or what he is has never been stated and still isn't known for sure to this day. In any case, after staying with Tom Bombadil for a while, Gandalf decided that the time had come for him to leave Middle-earth, as it was safe for the first time in a long time and in very capable hands. He had been sent to Middle-earth with the express purpose of defeating Sauron, and now that the mission had been completed, he was free to go back to the life he once had in Valinor centuries ago.
He departed for the Undying Lands along with the last of the Elves - such as Elrond and Galadriel - and was accompanied by Bilbo and Frodo as well. With a goodbye to the other Hobbits, they sailed away into the West and were never heard from again. This decision to leave wasn't made out of avoidance or any sort of laziness, as Gandalf had worked tirelessly for Middle-earth since the moment he got there. His goal was the defeat of Sauron, and once that was complete, he left the space for others to come and lead in the world, rebuilding it into something new.