Editing Rhine (section)

===Stream capture===
The watershed of the Rhine reaches into the [[Alps]] today, but it did not start out that way.<ref name="Ber">{{harvnb|Berendsen|Stouthamer|2001}}</ref> In the [[Miocene]] period, the watershed of the Rhine reached south, only to the [[Eifel]] and [[Westerwald]] hills, about {{convert|450|km|abbr=on}} north of the Alps. The Rhine then had the [[Sieg (river)|Sieg]] as a tributary, but not yet the [[Moselle]]. The northern Alps were then drained by the [[Danube]].

Through [[stream capture]], the Rhine extended its watershed southward. By the [[Pliocene]] period, the Rhine had captured streams down to the [[Vosges Mountains]], including the [[Main (river)|Main]] and the [[Neckar]]. The northern Alps were then drained by the [[Rhone]]. By the early [[Pleistocene]] period, the Rhine had captured most of its current Alpine watershed from the Rhône, including the [[Aare]]. Since that time, the Rhine has added the watershed above [[Lake Constance]] ([[Vorderrhein]], [[Hinterrhein (river)|Hinterrhein]], Alpenrhein; captured from the Rhône), the upper reaches of the Main, beyond [[Schweinfurt]] and the Moselle in the Vosges Mountains, captured during the Saale Ice-age from the [[Meuse (river)|Meuse]], to its watershed.

Around 2.5&nbsp;million years ago (ending 11,600 years ago) the Ice Ages began. Since approximately 600,000&nbsp;years ago, six major glacial periods have occurred, in which sea level dropped as much as {{convert|120|m|abbr=on}} and much of the continental margins were exposed. In the [[Early Pleistocene]], the Rhine followed a course to the northwest, through the present North Sea. During the so-called [[Anglian glaciation]] (~450,000&nbsp;yr&nbsp;BP, marine oxygen isotope stage&nbsp;12), the northern part of the present [[North Sea]] was blocked by the ice and a large lake developed, that overflowed through the English Channel. This caused the Rhine's course to be diverted through the English Channel. Since then, during glacial times, the river mouth was located offshore of [[Brest, France]] and rivers, like the [[River Thames]] and the [[Seine]], became tributaries to the Rhine. During interglacials, when sea level rose to approximately the present level, the Rhine built deltas in what is now the Netherlands.

The most recent [[glacier|glacial]] period ran from ~74,000 (BP = Before Present), until the end of the [[Pleistocene]] (~11,600&nbsp;BP). In northwest Europe, it saw two very cold phases, peaking around 70,000&nbsp;BP and around 29,000–24,000&nbsp;BP. The last phase slightly predates the global last ice age maximum ([[Last Glacial Maximum]]). During this time, the lower Rhine flowed roughly west through the Netherlands and extended to the southwest, through the English Channel and finally, to the Atlantic Ocean. The English Channel, the Irish Channel and most of the [[North Sea]] were dry land, mainly because sea level was approximately {{convert|120|m|abbr=on}} lower than today.

Most of the Rhine's current course was not under the ice during the last Ice Age; although, its source must still have been a glacier. A [[tundra]], with Ice Age flora and fauna, stretched across middle Europe, from Asia to the Atlantic Ocean. Such was the case during the [[Last Glacial Maximum]], ca. 22,000–14,000&nbsp;yr&nbsp;BP, when ice-sheets covered Scandinavia, the Baltics, Scotland and the Alps, but left the space between as open tundra. [[Loess]] (wind-blown topsoil dust) arose from the south and North Sea plain settling on the slopes of the Alps, Urals and the Rhine Valley, rendering the valleys facing the prevailing winds especially fertile.