Danube
Classified as an international waterway, it originates in the town of Donaueschingen, in the Black Forest of Germany, at the confluence of the rivers Brigach and Breg. The Danube then flows southeast for about , passing through four capital cities (Vienna, Bratislava, Budapest and Belgrade) before emptying into the Black Sea via the Danube Delta in Romania and Ukraine.
Battle of Ampfing (1800)
The French war goal, to occupy Vienna and force the Habsburgs to accept and comply with peace terms established in 1798, required a double-pronged invasion through northern Italy, which First Consul Napoleon commanded, and through southern Germany, a campaign that fell to Moreau. To secure access into Bavaria and, eventually, to Vienna, the French needed to control the Danube riverway. This was not a new tactic: this stretch of the river had been the site of major battles of the Thirty Years War and War of Spanish Succession. Between Ulm and Ingolstadt, the Danube grows significantly in volume, making it a wide and swift waterway. The Iller joins the Danube at Ulm, dumping massive amounts of water into the stream; at Donauwörth, the Lech enters the Danube. Neuburg, the first significant city on the river after Donauwörth, had been the family seat of the princes of Pfalz-Neuburg; taking it from a princely family of the Holy Roman Empire would be a blow to the morale and prestige of the Habsburgs, whose role it was to protect the small princely domains. Control of the bridges and passages between Ulm and Donauwörth, Neuburg, then Ingolstadt offered an advantage of both transport and prestige. There followed a series of battles and clashes along the Danube between Ulm and Ingolstadt. Once Höchstädt and its nearby bridges fell on 19 June, the French controlled the Danube crossings between Ulm and Donauwörth. Kray abandoned Ulm, and withdrew further downstream. The next French target would be Neuburg. After a day-long battle for control of the river by Neuburg, the Austrians withdrew. Lecourbe ordered his troops not to pursue, as nightfall was on them. The French now controlled access to the Danube, its tributaries as far south as Pöttmes, and the banks on the north side of the river.