How Long After the Civil war, were MONITORS Produced?

John Ericsson’s famous warship (the MONITOR) was a revolution in warship design. It was practically unkillable (by other warships of the time). Yet, it was not a good design for the open sea (too prone to take on water). My question; for how long after, were these types of ships made?
Were they still used for coastal defense, up till WWI?

They were built through the mid-1870s, I believe, and then kept on the Navy List for many, many years thereafter. A double-turreted monitor, the USS Miantonomoh, made a famous cruise to Europe in 1866. To quote Wiki, “Her departure in naval design caused considerable comment in the English press, and The Times exclaimed: ‘The wolf is in our fold; the whole flock at its mercy.’”

Quite a few were turned over to the states’ naval militias in the late 1800s. Some were recommissioned during the Spanish-American War for coastal defense in the (we now know unlikely) event of a Spanish attack on the U.S. mainland. Some, such as USS Amphitrite, also were recommissioned for WWI service. The last U.S. monitor wasn’t struck from the Naval List until 1937, IIRC.

The Royal Navy had monitors (considerably and almost unrecognizably advanced from Ericsson’s design) until even after WW2.

A point here is that the Monitor and monitors are not even close to being alike. Even by the end of the Civil War, you were seeing vessels much closer to WW2 warships coming off the lines, ships which could sail anywhere and kill bloody near anything. They were to the original what a Jet Fighter was to the Wright Brother’s original.

OK, that’s an exaggeration. But the point, she is made.