The meeting will be held on Friday at the Wisby Strand congress hall. The area around the building and parts of nearby Almedalen have been cordoned off.
A large police force is in place that cooperates with, among others, the Coast Guard. Drones will monitor Visby from the air.
"On the agenda are, among other things, Russia's war in Ukraine, but also how we should respond to the hybrid threats directed at us in northern Europe," says Jesper Skalberg Karlsson (M), Member of Parliament from Gotland who participates in the Swedish delegation.
There are ten heads of state and government – how big is this meeting by Gotland standards?
"It's huge, it's hugely important. I can't remember that we've ever had this kind of high-level meeting with Visby," says Jesper Skalberg Karlsson.
See more about this in the clip above.