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Under a weak assumption of the existence of a geodesic null congruence, wepresent the general solution of the Einstein field equations in threedimensions with any value of the cosmological constant, admitting an alignednull matter field, and also gyratons (a matter field in the form of a null dustwith an additional internal spin). The general local solution consists of theexpanding Robinson-Trautman class and the non-expanding Kundt class. Thegyratonic solutions reduce to spacetimes with a pure radiation matter fieldwhen the spin is set to zero. Without matter fields, we obtain new forms of themaximally symmetric vacuum solutions. We discuss these complete classes ofsolutions and their various subclasses. In particular, we identify thegravitational field of an arbitrarily accelerating source (the Kinnersleyphoton rocket, which reduces to a Vaidya-type non-moving object) in theRobinson-Trautman class, and pp-waves, vanishing scalar invariants (VSI)spacetimes, and constant scalar invariants (CSI) spacetimes in the Kundt class.

All solutions of Einstein's equations in 2+1 dimensions: $\Lambda$-vacuum, pure radiation, or gyratons