There's a dinosaur in the Fortress of Solitude.
I know this because I bought the Action Annual, within which is the two-page spread of the Fortress of Solitude. Within which Superman has a Hall of Trophies. Within which there is a dinosaur.
Just like the one in the Batcave. Only orange.
Now, this is fascinating to me. There's no story that I know of that would result in Superman having a dinosaur trophy. Is it, like Batman's, a robot dinosaur? Is it a real dinosaur, stuffed? Is it just a statue of a dinosaur, and if so, what the the heck is it doing there? We know how Superman just loves statues. And there are other statues in the picture, including ones of the JLA and of the Legion of Superheroes (which, by the way, should never ever by left out by an open window). So I'm guessing it's just a statue.
But why? Is Superman a copy cat? "The Batcave looks so cool, and my stupid Fortress looks like a Tastee Freez shack. Maybe I should get a giant quarter? With my own face on it? No, wait ... a dinosaur. An orange dinosaur."
No, Superman's too, well, unaware to try and be cool by copying Batman. If Superman cared about being cool, he wouldn't be Superman (or even Clark Kent). So this means there is only one possible explanation for why there's a dinosaur in the Fortress of Solitude.
It's a rule.
Yes, at one point, in some JLA meeting back in the Silver Age, while everyone was nodding off during one of Wonder Woman's tedious lectures on parliamentary procedure, some wag slipped through a motion that all member's private headquarters must have a life-size dinosaur of some sort. Probably Green Arrow. Because he's a sarcastic SOB and is rich enough to buy a used Tyrannazoid from the Museum of Nazi Robotics for a lark and shove it an unused corner of the Arrowcave, because, after all, no one ever visits the Arrowcave. Except Solomon Grundy, and he's not exactly what you'd call a severe critic of interior decor.
So, I'm personally assuming that the one in the Fortress is the same dinosaur suit with the fake kryptonite teeth that "killed" Superboy when the Legion was stranded on a planet and had to make a rocketship out of rocks while faking Superboy's death. Why they had to fake Superboy being eaten by a dinosaur with kryptonite teeth, I can't remember or imagine, except that it's in the Legion by-laws that at least one member must be cruelly deceived by the others in every adventure. Lightning Lad slipped that one past the other members while they were nodding off to one of Saturn Girl's condescending sermons about parliamentary procedure.
But where did the other members get their dinosaurs?
Aquaman probably snagged the one that Thanatos attacked Mera with, and had it stuffed with seaweed by a horde of obsequious octopodes (or whatever collective noun they travel in) for proud display in the Aquacave. "Now there's a yarn worth re-telling," Aquaman booms out when he notices visitors staring horrified at the stinkysaurus. "Did I ever tell you about my battles against Thanatos?" Meanwhile, the guests are trying to figure out whether they can hold their breath long enough to get to the surface if they make a break for it...
The Flash Museum, no doubt, has the mummified corpse of the hypersonic super-intelligent other dimensional dinosaur that he worked with in the JLA Archive Volume 4. Probably has its own exhibit, including photographs of the Flash with his wife and eggs. Visiting the Flash Museum is probably like drowning in strawberry milk and I bet Captain Marvel has a lifetime membership there.
Wonder Woman, unlike the guys, has some taste. Undoubtedly, she just ordered an Amazon flunky named Artzankraftia to produce a twelve-foot carrera marble statue of herself as "Dinosaur Woman" from Episode 16 ("Island of the Dinosoids") of the Legendary Super Powers show (you know, the one where Darkseid was always trying to hook up with her). Wonder Woman is no fool; she can use Robert's Rules as a deadly weapon and knows how to work a loophole to make herself look fabulous. As a dinosaur.
Green Lantern, being a total goober with no dinosaurs in his own Rogues Gallery, probably stole Tyrano Rex, the evolved dinosaur he fought with the JLA and Tommy Tomorrow in DC Special 27 in April/May 1977 and pretends it's, you know, his. Probably keeps the corpse in his basement, draped in his high school letterman's jacket and holding a empty keg near the foosball table.
The Atom? Heh, I can just hear it now: "Oh, I shrunk one and brought it back through the Time Pool. It's on that homey polymer molecule over there about seven microns. You can see it, can't you, Superman? Tell them!"
Oh, yes, Superman says, it's a real beaut, and winks at the camera.