I think we should state that this is the swamp that the Hall of Doom is located. In the episode Monolith of Evil, Solomon Grundy refers to the swamp of his origin simply as "The swamp." He doesn't distinguish it from the swamp the Hall of Doom is located in, which strongly implies that they are the same swamp.
In the episode Swamp of the Living Dead, Grundy says that he had never seen the witch in the swamp before, implying that he was familiar with the swamp. Obviously it's where the Hall of Doom is located so that could explain his familiarity with it, or it could be the fact that it's where his origins came from. Just a thought. To me it's not that much of conjecture, it seems almost crystal clear that it is. But what's everybody else think?
--Noah Tall 17:58, June 24, 2010 (UTC)
I changed it
After watching the episode again, I realize now that the swamp that transformed Cyrus Gold into Solomon Grundy is the same swamp that the Hall of Doom is located in. It was more than just strongly implied, it's confirmed.