Why was a more unified Germany seen as a problem or a threat by Metternich? What kind of government in Germany was created instead?

What happened in 1848 in Germany that involved Frederich William IV of Prussia?

Ifound this on google “the existence of agglomeration economies is central to the explanation of how cities increase in size and population, which places the phenomenon on a larger scale. the concentration of economic activity in cities is one reason for their development and growth.” i hope this you for what your looking for.