The Travelling Oasis

Travellers in the Raurin Desert, known as the Desert of Desolation, tell of the legend of the Travelling Oasis. Reputedly this oasis appears to those who have the favour of Khonsu, the god of travellers, when they need it the most. They say that after leaving the oasis the traveller can never find it again.
As the god of travel and the moon, Khonsu lends particular favour to those who travel at night under his light. In all the stories the oasis appears just as the moon is starting to light the night and then disappears with the dawn the next morning. All that remains is full waterskins and food in the traveller's pack, and the traveller is always exactly as far away from their destination as their supplies will take them, no matter how deep in the desert they were previously.
The oasis is always illuminated by the light of a full moon overhead no matter the time of month, the myth tells, and the wide cool body of water is surrounded by a lush lawn which gives way to the bushes, palm trees and fig trees ringing the oasis. The coconut palms and figs are always in full fruit with heavy crops. Peacocks stalk the lawn, beloved of Khonsu and Horus for the many eyes adorning their tail feathers representing their eternal vigilance against the forces of evil.
Some superstitious caravans refuse to travel the desert during the dark of the moon. Instead, they will time their trip to allow them to take shelter in the closest oasis on those nights, and spend the time making offerings and requesting Khonsu's protection. These caravans typically take even greater care of each oasis they stop at than the usual desert travellers, because they regard them as a gift of Khonsu, and they dare not do anything which might anger Khonsu for their mistreatment of his gift. Each permanent oasis is a representation of the travelling oasis, and they cannot risk doing anything which might make Khonsu decide not to allow them into the travelling oasis should they need it.