The 555-ton Zubr-class vessel is the world's largest hovercraft, and was designed to land tanks on hostile shores. It can carry up to 400 troops and is equipped with missile launchers.
The hovercraft glided ashore in Mechnikovo, Kaliningrad on a massive cushion of air as beachgoers snapped photos.
Then, paratroopers disembarked and asked those nearby to pack up their things and move.
Russia's Defense Ministry says it was an ordinary exercise, and questioned the presence of people at the base to begin with.
"Docking at the beach is a regular practice, what we don't know is what people were doing at the beach, which is within the military firing range," said Andrey Bespaly, a spokesman for the Baltic Fleet Western military district.
Locals said the base referred to is several kilometers away from where the hovercraft landed. No one was hurt in the incident.
"After the drill was over, the cordon was removed and the ship sailed back to its base," Bespaly said.