Descriptive Attribute	Value(s)
Preserved Height	South: 0.80 m. East: 0.73 m. North: 0.74 m.
Abuts	Locus 31.
Description	The four to five courses of sandstone boulders with some fieldstone inclusions is a different construction technique from the architecture directly above (Locus 31—Transition Foundation for Locus 20) and below it (Loci 29 and 30 —North and South Ashlar Foundations). It is possible that the cobbles may be part of an earlier construction that was reused as foundation for Locus 20. The severely limited space makes it difficult to determine what the function and possible architectural relationship this space might serve. It may be possible the south section is merely fill providing structural support for the mud floor (Locus 23). It is also possible that this is merely superstructure for the fieldstone wall laid in a Lincoln log technique of walls intersecting on a grid pattern.
Location	On all three sides of the Trench severely limiting the ability to excavate.
Bottom (m)	Closing elevation: 901.723 m.
Phase Description	Phase Pre-Site Phase I: Pre-Site Phase I
Definition	Boulder Foundation/ Possibly Earlier Construction
Underlies	Locus 31.
Combined with	Possibly Loci 29, 30, 31.
Overlies	Loci 29 and 30.
Top (m)	Opening elevation: 902.503 m.
Stage	Stage 1
Stage Description	Early construction of boulder and ashlar foundation walls.
Phase	Pre-Site Phase I
Bonds to	None.
Size	South: 0.69 m east west. East: 0.86 m north south-by-0.42 east west width. North: 0.78 m east west.
Architectural or Soil Locus?	Architectural