DiscoveryInterdimensional slingshots were invented almost a hundred years ago in Greenerth time. The slingshots were inveted by a man named Zino Peoairs. Zino was looking to create a mode of transport that could move harmonids across the Yonderverse in minimal time. After discovering ways of "launching" people through the cosmos at lightning speeds, he could break the space barrier and throw people through dimensional corridors, and out into the one the started in, but in a new location.
Access & AvailabilityInterdimensional slingshots, when they were used by many, many people who sought out vacations on District 1 planets, as these areas were popular thanks to their harmless locations and creatures, with scenic views. The slingshots were stationed worldwide, usually several located across each country, with more slingshots in more advanced countries like the Western District.
ComplexityInterdimensional slingshots are fairly complex, requiring immense power to shoot someone through dimensions and back into their home dimension while also maintaining their structural integrity. It took countless hours figuring out the physics, while physics in the Yonderverse is constantly morphing.
There was always the risk that the person using the slingshot would end up in a completely new dimension, but luckily
Thanks to the many risks that interdimensional slingshots present, people were overjoyed when a more functional and safer method of interdimensional transport was invented. This mode of transport involved ripping a hole through the dimensions, creating a small, safe corridor to a new location in the same dimension on the other side. This might take longer to walk through, but only by a few seconds, which people are more than happy to sacrifice if it means it'll be much safer.
Unfortunately, with a new mode of instant travel, interdimensional slingshots were quickly forgotten about, they were closed down, workers sought out new jobs, and quickly the slingshots were demolished and ripped apart for any resources to reuse.