For a scenic view, and an answer-page for Guess The World...
Captain Future uttered a relieved exclamation.
"Ah, there's what we're looking for - Skal Kar's stockade."
Ahead yawned a thousand-foot clearing that had been hacked from the jungle. It was surrounded by a wire stockade, to which were connected cables from a squat atomic electric-generator. The generator kept the wire stockade charged, and the gliding white gas-beasts that swarmed outside dared not approach it.
At the center of the clearing looked the mysterious laboratory of the murdered scientist. It was a black cement tower, windowless, cylindrical in shape. Curt brought the Comet down to an expert landing inside the stockade. He cut the cycs, then rose to his feet.
"Looks like the place is deserted," he told the Futuremen, "but we'll take no chances. Be ready for a scrap in there..."
Edmond Hamilton, The Magician of Mars (1941, 1968)
...I was watching a strange, unearthly scene. There was a whole crowd of men such as the one I had met. They were gathered around what looked like a huge wheel, at least fifty feet in diameter. This wheel was attached to a great mass of machinery by means of a large axle.
Hanging on the bottom of a wheel was a small egg-shaped vehicle. Set in the side of this was a circular doorway whose thick metal door was open. Before this was a being whom I instantly knew to be he whom I had met. The other people were gathering around him talking in an utterly incomprehensible tongue.
whole scene was set in a huge clearing before what looked to be a small
city of curious hemispherical buildings. The horizon of this strange
world was very close. The curvature could be distinctly made out. The
sky was a deep blue, and overhead, filling most of it, was a vast
Donald A Wollheim, The Man From Ariel (Wonder Stories, January 1934)