Would you like some watermelon?

すいか / スイカ (su-i-ka), watermelon.

The town-gas holder.
The gas company makes town-gas from LPG and hold it in this container.
Once 10 years, The paint of this container is come off and inspected. Then it is repainted.
The company painted it as a huge watermelon, because it is the special product of Takizawa Village where the gas-works (the container) was built.