Skray'Lyorn

Situated on top of the flying stone islands known as the Sky-Sworn Mountains, the long lost town of Skray'Lyorn was founded by cloud giants before being destroyed by disease and blight and abandoned.
The three inverted mountains soar over half a mile above the sand in the Desert of Desolation, making a slow five-mile orbit of a central point over the span of a year. The secret of their flight, and of their curiously flattened tops, has been lost to time. Attempts to more closely examine the mountains, and the jungle-covered lands atop them, have always been bloodily repelled by the gargoyles roosting on the craggy sides.
The cloud giants who founded Skray'Lyorn raised the mountains with the aid of their stone giant cousins, linking the three stone masses so they always remain closely together. The water source for all three is a Decanter of Endless Water built into a statue near the centre of the highest mountain. Water erupts from it into a pool, with irrigating waterways running across the flattened top of the mountain.

Overgrown Skray'Lyorn water cistern by rjayar

After reaching the cliff edges, the water is channelled through stonework which creates waterfalls. The waterfalls are carefully aimed at receiving pools on the two lower mountains, which divert into storage cisterns, which are full to overflowing after centuries unused. The cisterns release the water into streams irrigating each mountaintop, before flowing to the edges of the lower mountains and venting in their own waterfalls in turn. Although the water evaporates before it reaches the surface, the region underneath the mountains is slightly cooler, a little more humid, and supports far more life than the rest of the desert. At night, a fine cold mist can be felt descending from above.
Underneath the rampant greenery spread across the tops of the mountains lies the stone ruins of the town. Built to be a centrepiece of the cloud giant civilisation, it was filled with lush, ornate gardens, flowing pools, and animal menageries. Unbeknownst to the giants, however, some of the plants imported for the gardens were infected with Blight. The blight infected the fruit which the giants ate, and they were weakened and poisoned until they died out. The plants subsquently began to mutate into aggressive & carnivorous forms and spread, as did the animals which survived their exposure to the blight.
Now all that remains is the crumbled stone ruins hidden beneath the jungle. Watered by the irrigation channels, the mountains play shelter to plants and animals not seen anywhere else in the desert for centuries.