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Dwarf Fortress is a very complex game, and building the perfect dwarf stronghold could take days if not weeks. But sometimes you want to start over with some new ideas and a better understanding. So how do you start a new fortress in a dwarf castle?
Create a new fortress in the Dwarf Castle

First, you will need a world in which to create your fortress. Dwarf castle worlds can only have one active castle at a time. As a result, you will need to either create a new world, or finish off one of your previous castles. To do the latter, you can either retire or give up your current fortress in the world. This is done by loading the save of the fortress you want to end, pressing ESC, and then selecting either Castle retired (for now) or Abandon the castle to destroy it.
What does it mean to retire the castle in Dwarf Castle?
Abandoning a castle in a dwarf castle means giving up control of the castle and running it as an AI-controlled fortress in the background of the entire world. The Citadel will continue to exist, but it will also face potential challenges and attacks. You can also theoretically interact with it from your new castle, sending raids and invasions on it. A retired castle will keep its residents, goods produced, furnishings, and just about anything else. It can be unblocked as long as no other active fortress is saved.
How to remove the castle

To remove a fort, head to the Embark screen and tap s or click restore / unretire button. From here you will get a list of abandoned and retired castles. Select your retired fortress to start over. You will not be given any options to proceed, you will just jump back into your castle. However, don’t expect everything to be exactly as you left it.
What does it mean to abandon the castle in Dwarf Castle?
The abandoned castle is actually the “surrender” button in the dwarf castle. This is nothing to be ashamed of. Some castles are not worth saving. There is no point in waiting while the orcs spend the next few months hunting down every last troll, or while the forgotten beast eats every last cat. Abandoning the castle empties any surviving dwarves, and they return to their original civilization. It also clutters up your items. You will be able to play again in the world, but if you restore this castle, you will need to do so with the new dwarves.
Related: Tips, tricks and hotkeys you may not know in Dwarf Fortress Steam
Can I take back the forts I abandoned in the Dwarf Fortress?
You can restore abandoned castles by heading to initiation screen and press s or click Recover / Cancel Refund button. However, any enemies that may have captured your fortress will stay there. Some of your former residents may be there, though they won’t necessarily be friendly.
You will have to use the recovery command as the items will be blocked. This option is not for the faint of heart. Often you will need several waves of reclamation to clear the overrun fortress. However, one of the great things about Dwarf Fortress is that the world is static, and nothing is really finished.
One thing you can do is create a nearby castle, horde and army, and send them to investigate or attack the abandoned castle. This has a chance of removing any nasty creatures that may still be around, plus it can give your new fortress some great loot!
For more Dwarf Fortress guides, information, and more, check out Can You Dig in the Dwarf Fortress Aquifer? on Pro Game Guides.