"Ah, I was afraid you had become trothed Sonja, it's good to have your arm here."
"Hello boat, come to and show yourself. Be warned, if you try anything, you will have an arrow shaft in your chest before you can lift your bow!"
"Hush Bjarne, if I meant to harm to you and the garrison, you would be sprouting arrows from your eyes before you knew it."
"True that is, Sonja, while there are men that can shoot farther than Red Sonja, there are none that can shoot so deadly. I see you have come to drop off a keg of ale, good thing, we are nearly out."
"I'm here for my two weeks watch, Bjarne, and I need that ale for myself."
"Ah, I was afraid you had become trothed Sonja, it's good to have your arm here."
You live a good life, grandchildren. Many, many years ago, before your grandfather's grandfather's time, our households were often beset by raiders. Many times our men came back from a raid on the nearest fjord, only to find raiders from a different fjord had struck, burning the fields, taking the women and children, and stealing the cattle. The boats of raiders could pull up with no warning, with only a few women and young boys to fight them off.
Striking against our foes did not stop them, so wise men decided to set watch upon the narrows of the fjord near the mouth, at the Fjordthrotte. In the beginning, men just set camp on a small island, but with no protection from the sea, the waves soaked the kindling for the signal fire. With no protection from raiders, the men would often be overwhelmed before the fire could be started.
And so, a tower was planned for this little island. Stone by stone was laboriously sailed to the site, and in rough weather sometimes neither stone nor boat made it. The first floor took shape, a door that can only be reached by climbing steep, slippery steps, so no one can bring a ram against it. The door can be quickly barred, and is protected from axe bearers with spear holes.
The rest of the first floor is given over to a large fireplace to burn off the sea chill, a table for eating, and rooms for ale and provisions. Precious iron is used to hold spears and torches up and ready, for invaders can strike with little warning.
The second floor is a little drier, so a smaller fireplace is needed. Men grab a little sleep here, for with only six men and unmarried women guarding the tower, some one needs to be awake at all time.
Off the second floor is a small landing, were a guard, protected by parapets, can interrogate all boats that pass by. Any boat wanting to enter the Fjord had better stop and prove it's harmlessness, lest the signal fire be lit and armed men from deeper in the Fjord arrive in their boats. This door too can be barred, if any raiders are foolish enough to scale the tower to gain the landing.
The unsheltered roof supports the signal fire on a tower. The dry kindling is kept covered by a bear skin in bad weather, and oil is kept close to help it burn. Green branches are kept near it to throw on the blazing fire, to create a plume of smoke visible to the whole Fjord.
An accurate bow-man watching from above, and extras spears and piles of stone to drop on invaders complete the rooftop arsenal. The six mean can hold raiders at bay for days, since few northmen know of the art of seige equipment. Even if a raider gains entrance, the ladders can be pulled up to make the raiders pay in blood in for each floor.
In truth, the tower does it so well that no serious raid has happened in years. Most men and unmarried women look to their two weeks of duty as an occasion for fishing, drinking ale, socializing, drinking ale, and building camaraderie. There will be enough time for fighting soon, the crops are in, and ships and sailed are being mended for the summer raids to the fat, soft southern lands.