Substantial progress has been made in recent years on the 2D critical
percolation scaling limit and its conformal invariance properties. In
particular, chordal SLE6 (the Stochastic Loewner Evolution with parameter k=6)
was, in the work of Schramm and of Smirnov, identified as the scaling limit of
the critical percolation ``exploration process.'' In this paper we use that and
other results to construct what we argue is the full scaling limit of the
collection of all closed contours surrounding the critical percolation clusters
on the 2D triangular lattice. This random process or gas of continuum nonsimple
loops in the plane is constructed inductively by repeated use of chordal SLE6.
These loops do not cross but do touch each other -- indeed, any two loops are
connected by a finite ``path'' of touching loops.