Raft

"Give me a break, Barton. I had no idea they'd put you here, come on." "Yeah, well, you knew they'd put us somewhere, Tony." "Yeah, but not some Supermax floating ocean pokey, you know. This place is for maniacs, it's a place for-" "Criminals. Criminals, Tony. I think that's the word you're looking for. Right? It didn't use to mean me. Or Sam, or Wanda. But here we are."

- Tony Stark and Clint Barton

The Raft is an underwater prison created for the sole purpose of detaining and incarcerating enhanced and/or superpowered individuals.

History
After the Clash of the Avengers, Falcon, Scarlet Witch, Hawkeye and Ant-Man captured by Iron Man's team and taken to the Raft for working outside the law. Tony Stark flew to the Raft to tell Sam Wilson that he believes Steve Rogers' story about Helmut Zemo. Tony landed on the raft and was greeted by Thaddeus Ross. Stark made his way to where his former allies were being held. Tony was mocked by Clint Barton, but Stark tells Barton that they shouldn't be in there as the Raft was built for maniacs and criminals, which Barton claims that they are all now. Stark then walked past Scott Lang and made his way to Sam Wilson to ask where Rogers is so he can help him. As Stark was leaving, Ross asked if they said anything, which Stark lied about and made his way to Siberia.

Escape from the Raft
Later, Steve Rogers knowing he couldn't let down the people who stood by him, infiltrated the facility and freed Clint Barton, Wanda Maximoff, Sam Wilson and Scott Lang. Thaddeus Ross informed Tony Stark that there has been a breach at the Raft, while the latter ignored Ross' plea for help, allowing Steve and his Avengers to escape successfully.

Former Prisoners

 * Sam Wilson
 * Clint Barton
 * Wanda Maximoff
 * Scott Lang

Trivia

 * In the comics, the Raft is an island prison for super-powered criminals located near Ryker's Island.
 * This version of the Raft also replaces Prison 42, a massive prison located in the Negative Zone used by Iron Man, Yellowjacket and Mister Fantastic to contain non-registered superhumans as they waited for their trials in the original "Civil War" storyline.