Holding the festival at the military object, built by Swedish invaders, can be seen as a symbolic nod to the world overtaken by political and military tensions.
It's the military conflicts and the ongoing refugee crisis that made the organizers of Komēta to look eastward when inviting musicians, like Omar Souleyman, once the most popular wedding musician in Syria and now a refugee who fled to Turkey during the war.
On three evenings more than 40 musicians will take the stage at the Daugavgrīva Fortress. Their names aren't known in the world of the high and mighty, but that anyone acquainted with world music will testify to that they're top-notch, starting with reggae singer Rocky Dawuni, who was recently nominated for a Grammy.
"Music is one of the strongest weapons that will, I think, continue to be important in the 21st century. The concept of the festival is that we can travel across the world in one place – here," said organizer Dāvis Kaņepe.
And the journey will not be exclusively a musical one, with the French documentary filmmaker Vincent Moon being present as well.
"He has traveled the whole world, and during the 72 hours you'll be able to watch and go to Indonesia, Brazil, India, Ukraine, and more," said Kaņepe.
The constellation of world musicians at Komēta will be joined by local musicians like Jumprava. The main stage will be right beside the ruins of the ancient powder tower, while movie screenings and dancing will be held in the dungeons.
During the day people are invited to talk - about society, ecology, power and everything else under the sun.
The organizers hope that Komēta will see more visitors flock to the archaeological monument and revive discussion over the future of the Daugavgrīva Fortress.
Tickets are €25 for under-25s and €50 for the rest.