Descriptive Attribute	Value(s)
Location	Extending the length of the trench, except over the Locus 10 Platform landing and Locus 11 steps where it has collapsed into the West Cryptoporticus.
Combined with	Loci 2-17.
Size	Originally it must have extended the full 40.00+ m north south length of the West Stairway.
Phase Description	Phase IV: Nabataean Grand Design: 1st c. BCE to CE 1st c. The full Lower Temenos is constructed, complete...
Description	Locus 4 stands 1.73 m above the platform landing at the bottom of the Locus 5 Steps. At the south the entry is composed of four courses of well-hewn diagonally dressed sandstone ashlars. It is constructed in the casemate system with fill that is then faced with ashlars for 3.07 m to the south. At some point in antiquity this section of wall collapsed. It was subsequently rebuilt above one course of rubble fill 0.50 m in height (which originally may have housed a wooden beam to absorb the shifting in the case of earthquake), and above that there are three courses of roughly hewn ashlars—not those Nabataean regularly sized ashlars we are used to seeing with diagonal dressing. Some plaster, however, still adheres to the west face of this poorly executed wall indicating that its roughness in antiquity was hidden behind a plaster surface. To the south of this wall is a vertical split and the ashlars have slumped to the south. This suggests that its rubble fill middle bonding course has pulled away from the wall matrix and has collapsed. This wall and its repaired secondary wall replacement are placed in the same phase, for although the repaired section is noticeably different from the original wall construction, it was a measure taken to ensure the integrity of the stairway. As we cleared the platform landing of Locus 10, we also realized that the collapse had compromised the west wall, which had tumbled into the West Cryptoporticus. Ashlars as well as caution tape were put in place in the affected area to provide a barrier to discourage visitors from using this point as a lookout over the West Cryptoporticus, over a 5.00 m drop. We did this with the intention of preventing harm coming to tourists.
Top (m)	Opening elevation: 896.471 m.
Underlies	Locus 1 Debris Collapse and Fill,
Overlies	The West Cryptoporticus East Wall.
Preserved Height	The height for this wall varies and is dependent on its relationship to the stairs or platform. It averages 1.31 m in height, but it can range to 4.50 m in height.
Abuts	All stair and platform loci.
Stage	Stage 1
Cuts	None.
Phase	IV
Bonds to	None.
Bottom (m)	Closing elevation: 891.873 m.
Stage Description	Building of the West Entry Steps and Landing Platforms for West Bath entry.
Architectural or Soil Locus?	Architectural
Definition	Staircase East Wall (between Trench 98 to the east and the West Stairs)