A little complicated to set up, but basics are very well laid out, and it seems quite balanced.
It's essentially a fort with a ranged weapon?

This sounds nice. It would finally give the Brits a reason to have Gibraltar.

I like the concept, but a few suggestions...

I would make it a special weapon with prerequisites railroad gun and fortifications built in the province, rather than basing it on naval base... there have been plenty of costal gun emplacements away from forts, the guns sited at Calais and Dover during ww2 and the Gallipoli batteries that protected Istanbul in ww1 that the whole Gallipoli assault were all about being 2 examples of such. IRL, railroad guns have almost the same requirements and engineering involved in their creation, and many emplaced guns had short rail spurs to allow them to mask themselves behind emplacements during reload.

There also has to be a change in game mechanics for units that are engaged by coastal batteries to be able to keep moving and leave the engagement area rather than becoming bogged down in the fight until one or the other is destroyed... ships move, and the best defense against a coastal battery is to keep moving. This would also make the game more interesting to play, because it would allow players to build up convoys and try to run the gauntlet of the coastal battery to get into or out of water bodies that would otherwise become private ponds and still engage in amphibious assaults behind the batteries. If this were not implemented, batteries would be too powerful.

For upkeep, I think they should consume ALL materials, since they will have a disproportionate effect on gameplay if implemented, and need to be expensive as such.

Finally, they should have upgrade levels similar to fortifications, lvl1 being equivalent to a lvl1 destroyer's ship attack values and ranges, lvl2 a lvl5 destroyer, lvl3 a lvl1 cruiser, lvl4 a lvl5 cruiser, lvl5 a lvl1 bb, and lvl6 a nuke bb.

Hope these suggestions help, and would love to see them join the research tree!

-C

The gun in Norway was in fact an actual thing; came from a WWI Russian Battleship if I recall. Railroadguns typically were made from surplus Battleship parts anyway.

I like this idea; perhaps level 2 or three Fortifications could be a prerequisite for building them.

This is(more or less) how BB are loaded. Did you not know that?

I like this idea and always have, coastal artillery was always an important part of any nations defence up until the end of world war 2.

With reference to the previously mentioned coastal batteries built by the Germans as part of the Atlantic wall, 3 require special mention.

1. Austratt Fort in Norway which has the C Battery which had been intended for use on the Battleship Gneisenau mounted on a verticle shaft comprising ammunition rooms and power plants. These guns are 28cm or 11 inch and could fire a 780lb shell 38km.

2. Movik Fort in Norway, where four 38cm or 15inch Bismarck guns were mounted to cover the entrance to the Baltic. Each gun capable of firing a 1000lb shell up to 56km or an 1800lb shell 35km.

3. Trondenes Fort in Norway which has mounted 4 x 40.6cm or 16inch 'Adolf Guns' as they are known. These massive pieces of coastal artillery could throw a long range shell at a weight of 1300lbs up to 56km, alternatively the standard shell of 2270lbs could be thrown up to 42km.

I hope this little gif helps(if it works).

No problem.

I Like this idea was well. But i think you should be able to build it at a normal factory and not at the coastal city( it can but can also be build inland). Were it can be taken apart and shipped to the coast. To build it i should take level 1 industry level 2 infrastructure. however in order to place it there must be level 1 fort. There should be a dissemble time and a reassemble time. much like loading and unloading troops.

But should it be a secret unlock or an Armour unlock?


Also like "aDudeWhoDoesThings" original post so more people see read about these ideas that every one has on this

Haven't read all of it. But wouldn't it be better then, to replace the Fortification building on coastal provinces with a Coastal Battery instead?

Same range as a Battleship.
Add's defence value to troops stationed in the province, but at a much reduced rate, because you replace the defensive values with offensive values instead. Say, 5-10% per level defence, and a damage output similar or slightly higher than a group of Artillery or Railroad guns? Just a thought.
It'd mean that the province then can't have, say, Level 5 Coastal Batteries, as well as Level 5 Fortifications, which, if put together, with a defensive stack in place of, for example, anti air, anti tank, and anti infantry units, by extention make the provinces almost invulnerable. So for example, you build level 5 fortifications and level 5 coastal batteries all along your core provinces, and build enough troops to defend those exterior core provinces like it was trying to invade hell itself, you could, theoretically with that much defensive pre-planning, rebuild from any invasion from any player at any point in the game, short of high level rockets or nukes.

Some thoughts.
Coastal batteries are various things, from 155 mm/8 inch types of guns all the way up to 14 - 16'inch naval guns. There have been a TON of various cannons defending everything from ports to important islands through out history. Otherwise all we have is basic artillery which is inadequate. Maybe it is difficult for CoW to put them on the 'beaches,' as basic fortifications are in the center of the territory.
The basic guns could be only a few hit points (like the 10 hp arty for example) all the way up to 20 or 50 hp for the better emplaced guns (remember BBs have 75 hp) in the various type of bunkers. Coastal guns seem like a very good idea. They would cost way less than a ship.
As far as making them a part of a 'tech tree,' how hard is it to place a big gun in a 20' x 20' dug-out pit? Maybe the more detailed '2nd tier' (the part requiring research).
Btw thanks is due for the recent Tank Destroyers. Very well done CoW staff . We appreciate your efforts.
Please consider these additional units:
Convoy Raiding Units "The only thing that ever really frightened me during the war was the U-boat peril."- Churchill. Subs were mainly used for sinking freighters. In fact they were infrequently used to destroy capitol ships. They're missing 95% of their purpose.
It would be a simple thing to put convoy boxes on the map in the Western Approaches, Mid-Atlantic Gap, Eastern U.S. coastline, etc. and have subs or raiders destroy some enemy resources.
Armor that uses more than infantry does in manpower. Light & medium tanks take less than 1/2 of infantry units. They are the cheap 'magic' troop type. Everyone likes to play armor, and everyone buys it- simply for the low manpower. No offense intended, but this is not right. These 'corps' in the game should be using 20,000 to 40,000 soldiers (as set-up they are not regiments/ brigades). Armored corps have more soldiers than infantry corps. The Germans for example had the basic 4 (motorized/mech) inf. regiments AND 1-2 armor regiments. There were always inherent infantry within armored corps. I.e. MORE manpower required, not less than half.
Paratroopers (only a very limited amount country historically). The U.S. had the 82nd & 101st divisions & several lesser para regiments in WW2- no more. I.e. there should be limits.
Partisans (there were millions in WW2 on the Russian front for example). Hard to put in the game, but do-able.
Carriers (duh ) WW2 in the grand scale simply isn't correct without carriers (for example the U.S. operated 28 CVs & 71 LCVs by the war's end). CoW without carriers is like a WW1 game in the Pacific.
Thanks for reading this and considering these propositions.
Superb game CoW designers!