The European powers had military plans prepared for the event. The most well known is the German Schlieffen Plan and the French had Plan XVII. It's debatable if this means these countries foresaw the Great War or if they just considered another continental war a possibility and made plans for it accordingly.

The European powers had military plans prepared for the event. The most well known is the German Schlieffen Plan and the French had Plan XVII.

However, militaries draft many war plans that are never used, such as the United States's 1920s-30s war plan against the United Kingdom. See Estimate of the Situation - Red and Tentative Joint Basic Plan - Red (PDF - 139 MB).

The existence of war plans doesn't mean these countries foresaw the Great War, it's only in hindsite that they may seem prescient, but at the very least they considered a continental war a possibility and made plans for it accordingly. To use these plans as evidence that military and civil leaders forsaw the war, you'd need to learn more about their opinions and actions they took to prepare for or enact these plans.

John Keegan's perspective in The First World War: "In no sense did [Schlieffen Plan] precipitate the First World War; the war was the result of decisions taken, or not taken, by many men in June and July 1914, not by those of a group of officers of the German Great General Staff, or any single one of them, years beforehand. Neither did its failure, for fail it did, determine what followed; it was a plan for quick victory in a short war." (1998)