Short answers, pulled from the story.
The Rhine river begins in the Swiss canton of Graubünden where the Anterior Rhine and Posterior Rhine merge near Reichenau in Tamins. The Anterior Rhine springs from Lai da Tuma near the Oberalp Pass while the Posterior Rhine rises from the Paradies Glacier near the Rheinwaldhorn.
The Rhine first entered the historical record in the 1st century BC as the boundary between Gaul and Germania. The Romans established military camps along its banks starting with the founding of Oppidum Ubiorum in 38 BC which later became the city of Cologne.
The Middle Rhine between Bingen and Bonn is a section of the river recognized as a UNESCO World Heritage Site since 2002. This Romantic Rhine stretch contains more than 40 castles and fortresses along with the famous rock Lorelei and numerous vineyards.
The Lower Rhine flows through the North German Plain and is home to the largest conurbation in Germany known as the Rhine-Ruhr region. Major cities in this area include Cologne Düsseldorf and Duisburg which hosts Europe's largest inland port Duisport.
The Rhine descends over 1,000 kilometers from its Alpine origins at an elevation of 584 meters to the North Sea. It drains an area of 185,000 square kilometers and serves as a vital navigable waterway that has brought trade and goods deep inland since Roman times.
The International Commission for the Hydrology of the Rhine Basin warns that the river could experience a massive decrease in volume or even dry up completely within the next 30 to 80 years due to the climate crisis. The river also faces threats from pollution flooding overuse and political instability.