Short answers, pulled from the story.
Lower Egypt is the northernmost region of Egypt, consisting of the fertile Nile Delta between Upper Egypt and the Mediterranean Sea. The Nile splits into branches in this region, with principal channels reaching the sea at Rashid in the west and Damietta in the east.
In Ancient Egyptian, Lower Egypt was known as mḥw, meaning "north." Copts continued using related terms, Tsakhet and Psanemhit, both meaning "the northern part." Greeks and Romans called it Aegyptus Inferior or Kato Aigyptos.
Lower Egypt began to advance as a civilization after 3600 BC. Shortly after that date, new pottery related to Southern Levant styles appeared, copper use expanded, and Mesopotamian architectural techniques including sun-dried bricks and the arch became widespread.
The patron goddess of Lower Egypt was Wadjet, depicted as a cobra. After unification with Upper Egypt, Wadjet was paired with Nekhbet, the vulture goddess of Upper Egypt, and together they were honored as the Two Ladies, protectors of all ancient Egyptians.
King Narmer unified the two kingdoms by defeating his enemies in the Nile Delta during his reign over Upper Egypt. The event is commemorated on the Narmer Palette, which depicts Narmer striking down a figure named "Wash," though whether Wash was an actual king or an allegorical figure remains uncertain.
Lower Egypt was divided into twenty administrative districts called nomes, the first of which was centered at el-Lisht. The capital of Lower Egypt as a whole was Memphis, also known as Ineb Hedj or Men-nefer, located at the site of modern Mit Rahina.