Abatis Construction at Fort Lee
Fortifications were protected by obstacles, such as an abatis, or other major hindrances to assaulting troops. They were easily placed before a parapet, or breastwork, wherever trees were plentiful and were used to supplement defensive rampart walls or barricades.
Derived from the French word meaning heap of material thrown together, the abatis was built of piles of trees or large branches sharpened to a point and turned toward the enemy’s approach. They were entangled to form an impassable barrier for cavalry and infantry.
At Fort Lee, maps show than an abatis was placed to provide protection from an assault from the northwest exposure.
The use of an abatis either alone or together with other entanglements, led to an extensive tree-chopping program to supply logs for these obstructions and for battery emplacements as well as to provide timber for huts and firewood for cooking and heating.
Bastion
Maps show that the fortification built on the high ground to the west was rectangular in shape with bastions at each corner. It undoubtedly was built to provide additional protection to the important batteries on the bluff and to prevent their capture by a land assault.
Courtesy hmdb.org