The following account was recorded in the agent's log during your transmission: Massive, twisted pipes made of what looks like coral snake through a vast, naturally formed cavern, pulsing with a weird, iridescent energy that's kind of... hypnotic, I guess. The air's heavy with the smell of saltwater and something sweet, like tropical flowers, and it's weirdly humid, but the temperature's pretty stable. A perfect replica of the Gateway Arch has somehow been embedded in the ceiling, upside-down and backwards, like it just grew there, with water pouring down from the apex to create a perpetual, crystal-clear waterfall. Umm, the sound of it's almost musical, but it's got this weird, underlying drone to it.