Brwinów - a region of the great metallurgic centre form from the 1st and 2nd centuries AD with many thousands of single-use smelting furnaces found 50 cm under the surface of the whole small town. The photo shows a fragment with signs of melts from several score furnaces. The melted iron served to halt the expansion of the Roman Empire. West Mazowsze can be perceived as an economically leading settlement areas that directly influenced the political fate of Europe.