The Rhein-class monitor consisted of two ironclad riverine vessels, Rhein and Mosel, built by the AG Weser shipyard in Bremen between 1872 and 1874 for the German Kaiserliche Marine. Designed primarily for river defense, they measured approximately 47.85 meters (157 feet) at the waterline and 49.60 meters (162 feet 9 inches) overall in length, with a beam of 7.85 meters (25 feet 9 inches). Their displacement was around 200 metric tons at designed load, increasing to 283 tons at full load. The hulls were constructed with transverse iron frames, and the vessels featured a shallow draft—0.70 meters (2 feet 4 inches) forward and 1.07 meters (3 feet 6 inches) aft—optimized for river navigation, with a maximum draft of 1.60 meters (5 feet 3 inches). The ships were built with the capability to partially flood their hulls during combat, allowing only the upper casemate and gun turret to remain above water, minimizing exposure. Propelled by two horizontal 2-cylinder single-expansion marine steam engines, each driving a 0.95-meter (3 feet 1 inch) screw propeller, the ships achieved a top speed of approximately 6.5 knots. Steam was supplied by two locomotive boilers, and the engines produced around 320 indicated horsepower. Their maneuverability was limited, especially when steaming downstream or against currents, and they were known to handle poorly in turning, particularly when flooded for combat. Armament comprised two 12 cm (4.7-inch) bronze rifled, muzzle-loading guns mounted in a single revolving turret on an armored casemate amidships. These guns fired 36-pound projectiles and had a supply of 300 rounds. The armor protection included 55 mm (2.2 inches) of wrought iron on the turret sides backed by 150–200 mm (5.9–7.9 inches) of teak, with turret roofs 65 mm thick. The casemate was protected by 65 mm armor, with sides backed by 15–20 cm of wood planking. The ships' armor and construction reflected their intended role in river defense, notably to safeguard strategic bridges along the Rhine. Commissioned in 1874, Rhein and Mosel served briefly in the defenses of Coblenz from 1875 before being withdrawn from active service, as the threat of French attack receded. Their service was short-lived, and they were sold for scrap—likely in December 1884—marking their brief but notable role in Germany's riverine military capabilities during the post-Franco-Prussian War period.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.