The whole fortification is a circle of half a meter in diameter, and the outermost side is a circle of deep trenches, and the inner side of the trench is an earthen embankment made of earth, and there is a flat trail on the top of the earthen embankment, which can be used by the defenders to move and attack the enemy from a high position.

Inside the earthen embankment was an open space for the assembly and movement of troops. A nest was dug down in the middle of the clearing, which was used for the garrison and the storage of shelter and food supplies.

The reason why it is designed in this style is that the protagonist is to determine the plan after fully considering the difficulty of construction and the defensive effect.

In terms of construction, the construction difficulty, quantity and duration of the entire project are not a problem for ants who are good at civil work.

There are three main types of fort construction: digging holes, digging pits and piling embankments.

Digging holes is the old business of ants, all the main and secondary nests are built by digging holes, most of the nests are dug in the soil, and there are also peculiar secondary nests such as "Linshui City" that dig tree holes. Therefore, it is easy to find any ant in the burrowing operation.

If you dig a trench with a trapezoidal plane with a cross-section of the upper width and lower narrowness, according to the data of the width of the top of the trench, the width of the bottom half a decimeter, and the depth of one decimeter, the total amount of earthwork is only 15 cubic decimeters.

These earthworks can fill a 15-liter container, which weighs about a few tens of kilograms, and is not difficult to complete with the construction capacity of the ants. As the saying goes, "the embankment of a thousand miles collapses in an anthill", it can reflect the amazing digging ability of ants from the side.

The seemingly simple task of piling the embankment is the most difficult part of the whole construction.

It is enough to pile up the earth excavated during the digging of holes and trenches on the inside of the trench to form a trapezoidal earthen embankment with a cross-section.

However, simply piling up the soil particles will inevitably cause the mound structure to loosen, and it only takes one or two rains on the scale to completely break the embankment. In order to avoid this situation, the protagonist can refer to the wisdom of the ancient Chinese.

When ancient China was building buildings, a technique called "rammed earth" was developed according to local conditions. Rammed earth, also used for ramming, that is, using various tools and means to compact the soil to form a kind of material strong, dense and less crevice pressed mixed mud block, used as a building.

This technique has been used on a large scale from the Neolithic period to the fifties and sixties of the last century, and even now it is still used in some remote areas.

The general method of rammed earth is to use dry base to tamp the soil layer in layers, which is a kind of high-intensity manual labor that requires a large number of laborers, ranging from thousands to tens of thousands. The foundations of ancient buildings such as the Great Wall, the Forbidden City, the Mawangdui Han Tomb, and the Mausoleum of Qin Shi Huang are all rammed earth.

The rammed earth method does not pick materials, the clay under the fortress is enough to use, and there is no shortage of ants in terms of labor. The only difficulty is that rammed earth requires a large tool such as stones to tamp the loose soil layer.

Although ants can lift objects hundreds of times their own weight, given their small size, the small rocks that several ants can lift together are simply not enough to bear the heavy task of ramming earth tools. When a stone of this weight hits the mound of earth, it leaves a small pit.

Fortunately, the ants carry a construction adhesive that binds the loose soil particles together.

In the real world, for example, there are a large number of ant and termite "skyscrapers" on the African continent - ant mounds.

Ant mound, also known as ant hill, English for anthill, is an ant nest built by soil-dwelling ants that is high above the ground into a tower-like nest, and is called an ant mound because of its resemblance to a mound.

Many soil-dwelling ants or termites choose dead trees or shrubs to build their nests, and ants and termites will first bite off the soft parts of the plant, leaving only the hard wood as the skeleton; Then, thousands of ants and termites, carrying grains of sand and soil, climbed up to the skeleton and built the soil grains on top of it with saliva and feces.

Sand and soil particles play the role of "bricks", and the saliva and feces of ant termites are good binders, like "cement", which firmly glue the "brick layer" together. Whether it's termites, black ants, or red ants, their saliva and droppings are mixed with sand and soil particles to turn them into building materials that are comparable to the strength of "concrete", and they are not afraid of storms and rains.

As the "brick walls" continue to grow taller and thicker, the "walls" are connected according to the natural form of the tree skeleton, separating large and small "rooms". The construction speed of the ant mound is very amazing, and one cubic meter of ant mound can be built in ten days. As the colony multiplies, the mounds also increase year by year.

When the protagonist was a child, after reading the story of African ants building ant mounds, he was once in a state of flux, and he was determined to let Chinese ants catch up and never lose to the ants of the third world in Asia, Africa and Latin America.

So he picked up the plasticine and other materials at home, and pinched a "building" on top of the exit of the ant nest in his backyard, which was barely called a tower, and forcibly let these ants live in this "ant mound".

As a result, it was naturally a failure, although the protagonist fought against all kinds of adults and kept the "ant mound" from being demolished. But these ungrateful ants actually opened another entrance and exit, and they would never live in the "ant mound" that the protagonist had worked so hard to build, making him half angry.

But at this moment, the protagonist is still grateful for his childhood foolish behavior, and has learned a lot of knowledge and experience for this.

If the saliva and feces of the big-headed ants mixed with clay particles can be as strong and malleable as "concrete", then the construction process of "Dongyang Castle" will make a huge leap. The protagonist decides to experiment as soon as he gets back.

Defense is the main consideration for the protagonist when designing this fortress.

Although this fortress is simple, it is completely designed for the combat characteristics of parasitic ants, which can greatly weaken the threat of parasitic ants.

The difference in height between the bottom of the trench and the top of the embankment is only two decimeters, and there is a 45-degree inclination to ensure the stability of the foundation.

This angle and height is tantamount to flat ground for parasitic ants that are good at climbing, but for the silk thread parasites on the back of parasitic ants, once they are separated from the host, they cannot overcome this height by their own ability.

During the last failed expedition to the parasitic ant nest, the protagonist discovered that several squads guarding the cliff were largely undisturbed by the silk parasite in the initial defensive battle, while the fighters from other directions suffered from it.

As long as it can block the unstoppable attack of the silk thread parasite in the dark, then it is not so easy for a parasitic ant with strong individual combat effectiveness to defeat the Divine Envoy King Legion with strict discipline, strict organization and exquisite tactics.

That's the biggest role of this fortress.