Ukonvasara is a very special type of hammer that was traditionally used by the people of Finland. Think of it like a toy hammer that you might use to play pretend or fix things around the house, but much bigger and stronger!
The word "ukonvasara" means "thunder hammer" in Finnish, which is a really cool name. It is said to have been used by the Finnish god of thunder and lightning, called Ukko, which makes the hammer pretty special!
People in Finland used the ukonvasara for many things, like building homes and boats or making tools and weapons. They would have to hit the hammer really hard against objects to make them shape into what they wanted.
What makes the ukonvasara unique is its shape. It has a flat and round head that is sort of like a pancake, and a long handle that you hold on to. This shape helps distribute the force of the hammer's blow evenly, so that it doesn't break or damage the object being worked on.
Nowadays, the ukonvasara isn't used as much as it used to be, but it is still an important symbol of Finnish culture and history. If you ever visit Finland, you might see the ukonvasara on display in a museum or even see people using it at festivals and events.