Tourist destinations of the Great Wheel
Mechanus: The Grand Museum of Law and Order. It consists of a single 10' x 10' x 10' cube of a room with a sheet of paper and an equation written on it, which a nearby modron is tasked to explain is the fundamental rule that underpins all existence, thus proving that law and order came first and foremost. There is no gift shop, because the knowledge of law's perfection is the gift.
Arcadia: The Harmonious Hall of Education and Concordance is always happy to have visitors, staffed as it is by eager low-ranking members of the Harmonium who want very much to convince you that their beliefs of a perfect and orderly multiverse are inherently superior to anything else. It does have a gift shop, but everything is absolutely tacky for anyone who isn't already a hardcore believer.
Mount Celestia: The Silver Shores Grill is an excellent place to stop, located beachside in the first of the heavens; the main chef is a reformed mezzoloth, and their greatest delight is preparing exactly the dish you wanted, whether or not you knew you wanted it. There's no menu, and the waiting time is usually under five minutes from being seated to being fed.
Bytopia: The Auditorium is a wandering performance hall carried on the back of an absolutely absurdly oversized squirrel. The inhabitants have open mic night every single day, and you're invited to take part. They're more than happy to let you sit in the audience, too, and sell mildly rotten tomatoes for a copper each. The gift shop is full of both absurd prank nonsense and thoughtful volumes on the history and practice of comedy.
Elysium: The First Spring Salon sits at the headwaters of the planar river Oceanus, and is a full service salon, spa, and wellness retreat. Nearly any entity imaginable, save for those fiendish sorts who wither on contact with the plane's energies and undead vulnerable to holy water, can be found relaxing here. There is a gift shop, and it sells the best skincare kits to be found across the planes.
The Beastlands: The Changer's Way is a park handled by a pair of enterprising druids who use their own magic and the nature of the plane to let visitors experience what being an animal is like for a day. There are waivers to be signed that if you get eaten, it's your own fault and that you agree to accept whatever form they reincarnate you into, no matter how absurd. The gift shop is whatever twigs and rocks you collect as a beast.
Arborea: It's just called Barry's. Ask the locals where to find it, because no one from outside the plane will ever stumble onto it by accident. It's a pub run by a satyr with a corgi hound archon as the main waitstaff. The drinks and food are amazing, and you never end up with a hangover afterwards. There isn't a gift shop, but you can buy a commemorative tankard.
Ysgard: The Hotel at Branch's End is situated in a crook of the World Tree, and has a steakhouse, brewery, and set of divinely heated springs that are all part of the experience when you arrive. Just be careful about any ravens, they like to task drunks with legendary quests. The gift shop mainly sells spice blends and drinking horns.
Limbo: The tourist destination is whatever the person with the strongest imagination cooks up, and the gift shop will probably result in a pocket full of water.
Pandemonium: The Caver's Race Course is, oddly enough, a windboarding experience, where experienced locals will take sufficiently wealthy individuals on an aerial tour of the miles-long winding circuit. For an added fee, they'll provide enchanted earplugs to keep the wind out. There is no gift shop, on account of it having blown away again.
The Abyss: Grazz't's Bar and Grill is a perfectly nice place to get a meal if you happen to be in the area. The bartender is a fallen solar whose divine weapon still has enough sacred energy to keep the local fiends from getting too rowdy, and she has a strict policy that no souls are to be stolen, sold, traded, or tricked away on the premises. Surprisingly, Grazz't does indeed dine here, and enforces the rules. The gift shop mostly sells spice blends and soul larvae.
Carceri: The Last Hope is a fortress built by angels ages ago, meant to be a beachhead for an invasion of the prison plane. Staffed entirely by the locals these days, who are happy to give guided tours while trying to get you to sell your soul to them. It's not a great stop, but that's Carceri for you. The gift shop exists, and everything in it costs your soul.
Hades: Yeah, no, sorry, there's nothing worth it here unless you like depression and the color grey. Well, other than the Museum of Misery, run by a pair of dust mephits who've spent centuries cataloguing every form of mortal sorrow, despair, and suffering. It spans dozens of leagues at this point and they're constantly building onto it. The gift shop is present but totally empty, since disappointment is a form of misery.
Gehenna: Magdul's Marvelous Mountainslide is an arcanoloth-run toboggan experience that sends you hurtling down a volcanic slope on a course that changes hourly due to volcanic flows. There's a strict policy of no refunds and that you agree to any dangers inherent in the experience, and a clause that if you die on the course Magdul gets to keep your soul. The gift shop sells soul-infused obsidian and pumice, and replica toboggans.
The Nine Hells: There are a great many lovely tourist destinations in the Nine Hells, but the only one that doesn't literally cost your soul to experience is a gymansium in Dis that has no signage, with only an unmarked scorching hot door. If you can find it, you're allowed in, and if you can survive the equipment you're accepted. The interior is red-hot, and all the workout equipment is similarly hot iron and steel. The showers produce jets of boiling unholy water.
Acheron: Master Menzenno's Marvelous Mystery Mashup is a scrapyard run by a salt mephit, where they charge you for everything you find as salvage, assigning prices on a whim. Worth it mainly for the chance of finding lost artifacts and forgotten magic items, which Menzenno pretty much always vastly underprices. The entire place is the gift shop. Beware of rust monsters.
The Outlands: The Cafe is situated at the innermost ring about half a mile from the base of the Spire. It's a coffee shop and library, and they do a reasonable business among people who really want to just have a quiet place with a cup of coffee and a nice book, where no one will bother them. Run by a god of knowledge who abandoned her duties millennia ago and survives by the faith and gratitude of those who patronize the shop, with a side of the way the laws of the cosmos are thoroughly suppressed there. The gift shop sells mugs, tea, and coffee.
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