Star Forts

These forts really were impregnable. If you had a fort like this, you forced your adversaries to engage in some other sort of warfare.  Of course the problem with static defense is that it makes you rely too heavily on the bricks and mortar or on the technologies that were dominate when you built the structure. You don’t adapt to changing conditions both because you trust your existing protection and because you have so much invested in it that you really cannot easily change. Most of the great infrastructure of war is never conquered, but it is often bypassed or overtaken by changes. The smart opponent doesn’t attack your strength but searches for weakness.

They told me that the fort in Macapá is the largest of its kind. I don’t know if that is true; it isn’t that big but I have not seen many other star forts. I am also a little leery of the that term “of its kind.”  Maybe it’s the largest of its kind in Macapá.  I don’t know. Star forts have walls that point out like tips of a star. This was a response to artillery. Medieval castles have straight walls, since you could repel attackers from any point and they could attack from any point. The problem is that there are blind spots that cannot be adequately protected from any of the castles towers.  This doesn’t matter if your attackers are using swords, spears or pointy stick. It matters if you enemy can bring artillery to bear on your walls and if you have artillery of your own to direct against them. What the star fort does is fill the blind spot space so that anywhere that the enemy could approach is subject to interlocking fields of fire from the various points of the fort. The walls are also sloped so that projectiles will tend to glance off instead of just slamming in as they did with a medieval wall. The walls are also lower, since you can presumably put your adversaries under fire from a long way off. 

This type of fort worked well until artillery power, range & accuracy improved. It is the characteristic colonial fort of the Spanish and Portuguese. An example of a star fort in the U.S. is Fort Ticonderoga.

The fort in Macapá controls the main mouth of the Amazon. I didn’t know this, but the river that comes out at Belém do Pará is technically not the Amazon. It has the same water, of course, but in going around an island it gets a different name. The Amazon empties into the Atlantic at Macapá.