North:

To the north was the Mediterranean Sea. Egypt emerged as a civilization really, really early, around 3500 B.C. Europe and the Middle East was no where near being civilized at this time. Because of this, the Mediterranean Sea was basically a vast natural border that no one could cross. Egypt never had to worry about anybody attacking from the sea because no one had the ability to cross it. Their ships could not transport soldiers. As a matter of fact, outside of Egypt, no one knew about Egypt.

Having a natural border like a sea or an ocean, which is not the case here, is a tremendous advantage. The sea is flat, there is no hiding out there. So, lookouts could see for miles upon miles. Even if an invader wished to attack from the sea, the time period it would take to land would be enough time for the Egyptians to prepare and defend themselves.

The most difficult military tactic, even today, is the amphibious landing. Landing from the sea to the land is something armies today try to avoid because of the casualties they would encounter. First of all, there is no retreat. Secondly, running in sand makes you slower, therefore, the attackers would be easy targets. Lastly, the Egyptians in this case would be able to prepare heavy barriers and traps to stop and slow down the enemy even more.

West:

To the west of Egypt is the Sahara desert. The desert is a tremendous advantage. No one lives in the Sahara desert. It is a very severe place to live. Crossing the Sahara desert is absolutely impossible. Why? The Sahara desert is as large as the continental United States. No one could sustain moving an army across the desert. If they could, they don't really need to attack Egypt through the desert in the first place.

Also, the desert like the Mediterranean Sea, guards could see enemies from miles and miles away.

South:

To the south was the Nile river. The Nile River is very unique. It is the only river in the world that flows north. It makes it confusing to some because Lower Egypt in found in the north and Upper Egypt is found in the south. They refer to the source, not the direction. Because the Nile flows north, the Egyptians would use the current to their advantage. If an opposing army wished to attack from the south, the guard posts would sent boats up the river.

The current is faster than men on foot, so the Egyptians were able to squash attacks from the south rather quickly. Also to their advantage was the fact that very few people live south of Egypt. The people that did live in the south we not advanced enough to make a major attack on Egypt anyway.

East:

The east was a lot like the north. There was a sea and all the physical problems of landing were still there. However, the Red Sea did have some unique geographical enhancements. Across from the Red Sea is the Arabian Peninsula. It is a desert, but not as severe as the Sahara. For an army to march down the peninsula, board boats, and then try to attack would be foolish.