The player travels through here through a train at the start of the game, where they first meet Ame, the manager of the Reborn League. You also meet the Ghost gym leader Shade, although he's not named until later.
The player later travel through here to obtain the Alloy Badge. The gym is located north of the desert in 1R253 Scrapyard. If you didn't fight Taka at the Water Treatment Center, you will fight him here and after his defeat he offers to tag along with you throughout the desert.
The Mirage Tower is located in the east of the desert, above the Sugiline Ruins, and only accessible after finding three oases in the desert. If not, you can find TM27 (Return) and some poisonous lakes.
You must find a multiple of 3 Oases, otherwise it won't appear(e.g. 4 or 5 oases).
Inside the top building of 1R253 is a runaway nurse from the Orphanage called Stephoscope (she reconizes you since fought her before in the City Orphanage). She needs a nearby reliable source of water for the desert inhabitants. Explore Teknite Cave until you reach the room with a body of water then report back to Steph to be rewarded with Houndoomite.
Named after reborn's developer Marcello, there is a lemonade stand west of Mirage Tower. You can find it by walking behind the tower then go up and to the right. He will sell some Lemonade and if you defeat the Alolan Exeggutor next to him, it will drop a Dragonium Z.
Due to the fact that encounter rates will always change depending on where an oasis is located at (there are 4 possible locations), most rates will be ??? unless a pokemon will always appear at a specific encounter rate
Tourmaline Desert is named after the crystal, Tourmaline.
According to the merchants in the 1R253 Scrapyard, Titania used to hold Gym Battles there instead of in her castle.
Taka has additional dialogue if you bring him to the lemonade stand, however it is impossible to normally see it due to TMX Surf and Fly being disabled when with a partner. You need to surf behind Mirage Tower to access the stand, so the only way to bring Taka is through cheats.