The foundation trench with the cut stone blocks at about 10-ft intervals in the stockade trench and in Units EI and EII was part of the Grenet store's facade along Houston Street. The large foundation trench and its square termination found in Unit A is the end of the wall of the main store building, with a large buttress to help support this wall. The portion of wall foundation in Unit D is the corner of the north gateway with the inner wall of the northern line of warehouses, and the disturbance at its end is probably the position of a large timber which formed the corner framing of the warehouse. Even the cobblestones of the entrance roadway were found.
That we have a very good idea of the disturbances produced by the construction of Grenet's store is readily apparent. Thus it should be possible in future excavations to anticipate these and to recognize them as they are found.
The Phase I and Phase II excavations at the north wall have clarified certain aspects of the history of the mission and provided insight into the Battle of the Alamo and the defenses of the north courtyard. From the earliest period of the mission, excavations in Units E and EII encountered sections of an acequia, presumably associated with Acequia Madre West, and part of the temporary convento built around 1724. These discoveries indicate that this section of the Alamo contains important archaeological deposits dating to the poorly understood first years of the mission.
The discovery of the in-filled defensive trench paralleling the 1926 wall corroborates Mexican maps of the north courtyard. The available data suggest that this trench was filled two months after the end of the Battle of the Alamo. It is likely that, in addition to the human skull discussed earlier and in Appendix B, there are other human remains or artifacts from the battle used as fill in this trench.
The excavations also confirmed that the North Courtyard's 1836 surface had been disturbed or leveled sometime after the Battle of the Alamo, presumably by the U.S. Army. Features apparently associated with the army's occupation include the third ditch, dug ca. 1847, encountered in Units E and EII and the footing trench which crossed this ditch after it was filled in ca. 1851.
The most important conclusion drawn from this project is that the north courtyard and north wall areas of the Alamo contain intact archaeological deposits dating to the early occupation of the mission, the 1836 Battle of the Alamo, and the subsequent U.S. Army occupation of the mission. Any future modifications to the area that involve subsurface disturbance should require archaeological testing.