What was unusual about the territory of prussia as it existed in 1865?

What was unusual about the territory of Prussia in 1865?

In 1865 the territory of Prussia was separated into two sections by the Kingdom of Hamburg and the Danish held Schleswig-Holstein. These would be annexed by Prussia in the 1866 Austro-Prussian War uniting the entire area.

Well yes it is true that initially the Compromise of 1850 appeased both North and South enough to keep them from physically fighting each other, but of course this did not last for long, since no compromise was ultimately able to avert the Civil War.