The "second Ruhr" was a World War II area that included the "southern regions of Germany, the plateau of Bohemia

Bohemia

Bohemia is a historical region in central Europe, occupying the western two-thirds of the traditional Czech Lands. It is located in the contemporary Czech Republic with its capital in Prague...

, and Polish Silesia" where Nazi Germany

Nazi Germany

Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...

 military production was dispersed away from Allied

Allies of World War II

The Allies of World War II were the countries that opposed the Axis powers during the Second World War . Former Axis states contributing to the Allied victory are not considered Allied states...

 bomber bases in England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. After Allied Operation Pointblank bombing of German aircraft facilities had begun, Nazi Germany

Nazi Germany

Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...

 dispersed the 27 larger aircraft works across 729 medium and very small plants (some in tunnels, caves, and mines), and oil production

Oil Campaign of World War II

The Allied Oil Campaign of World War II was directed at facilities supplying Nazi Germany with petroleum, oil, and lubrication products...

 was also dispersed (e.g., Blechhammer

Blechhammer

The Blechhammer area was the location of Nazi Germany chemical plants, prisoner of war camps, and forced labor camps . Labor camp prisoners began arriving as early as June 17, 1942, and in July 1944, 400-500 men were transferred from the Terezin family camp to Blechhammer...

). However, by October 1943, long range bombers could reach the area (e.g., Marienburg

22nd Air Base

The 22nd Air Base is an Air Force Base east of Malbork, Poland, near the village of Królewo Malborskie. It was officially constituted on 1 January 2001, replacing the disbanded 41st Fighter Aviation Regiment...

).