The two-dimensional steady incompressible flow in rectangular cavities is c
alculated numerically by a finite volume method. The flow is driven by two
opposing cavity side walls which move with constant velocities tangentially
to themselves. Depending on the cavity aspect ratio and the two side-wall
Reynolds numbers different flow states exist. Their range of existence and
the bifurcations between different states are investigated by a continuatio
n method accurately locating the bifurcation points. When both side walls m
ove in opposite directions up to seven solutions are found to exist for the
same set of parameters. Three of these are point-symmetric and four are as
ymmetric with respect to the center of the cavity, if the side-wall Reynold
s numbers have the same magnitude. When the walls move in the same directio
n, up to five different flow states are found. In this case only a single m
irror symmetric solution exists for equal Reynolds numbers.