Final Fantasy 16 may not offer a completely open world, but it does offer many different regions that players are allowed to revisit and any time and explore. Many side quests and hunts will have players revisiting previous areas, and fast traveling can make this process much easier.
As you explore Valisthea, you will come across Obelisks, which can be used to further Clive's ability to fast-travel within a specific region. Upon entering a region, you'll need to explore more to find other Obelisks in order to fast-travel to them later on.
Local Map And Obelisks
To fast travel, simply open up the world or local map and select whichever region or Obelisk you want to travel to by holding down "X." As you explore a specific region, you'll find Obeliks that will light up with blue energy once you get close enough. After an obelisk has been lit up and activated, it will forever be turned on and can be fast-traveled. While exploring or not being in the middle of a main mission, you can open up the local map at any time and fast-travel to any discovered Obelisk.
The Local Map is a map of whichever region you are currently in. Each Local Map isn't very large, with some having more Obelisks depending on the size. On the local map, you can also see the border for the region, and approaching it will open up the world map to have you leave your current region. You can also at any time open up your world map and travel out of your current region without having to run back to the border.
Fast-Traveling On The World Map
As you progress further into the main story, different regions will be opened up for you to travel to. Traveling to a region for the first time will have you arriving at the start of the region and exploring it as a part of its respective mission. After exploring a region, it can be returned simply by traveling to it using the World Map. For any region, you can also open up its respective local map by holding down the touchpad while hovering over that region in the world map. Opening a region's local map can have you fast-travel to a specific Obelisk within a different region without always starting from the beginning.