Steam Shipyard

When Brunel launched the iron-hulled SS Great Britain and the Monitor traded shells with the Merrimack in Hampton Roads, the age of wooden sail was finished. The Steam Shipyard produces the Industrialization Age's iron warships and steam destroyers — vessels that laugh at wind direction, maintain formation in any weather, and carry enough coal to cross entire oceans without stopping. Their rifled guns outrange anything a sailing warship mounts; their armor shrugs off broadside shot that would splinter oak. Building this yard signals industrial naval supremacy: your opponent's sailing fleets become obsolete the moment your iron hulls slide into the water. Site the yard behind a coastal fortress for protection, fuel it with coal from your mining operations, and use its output to sweep the seas clean of older-era warships.