  We study the kinematical characteristics and 3D geometry of a large-scale
coronal wave that occurred in association with the 26 April 2008 flare-CME
event. The wave was observed with the EUVI instruments aboard both STEREO
spacecraft (STEREO-A and STEREO-B) with a mean speed of ~240 km/s. The wave is
more pronounced in the eastern propagation direction, and is thus, better
observable in STEREO-B images. From STEREO-B observations we derive two
separate initiation centers for the wave, and their locations fit with the
coronal dimming regions. Assuming a simple geometry of the wave we reconstruct
its 3D nature from combined STEREO-A and STEREO-B observations. We find that
the wave structure is asymmetric with an inclination towards East. The
associated CME has a deprojected speed of ~750+/-50 km/s, and shows a
non-radial outward motion towards the East with respect to the underlying
source region location. Applying the forward fitting model developed by
Thernisien, Howard, and Vourlidas (2006), we derive the CME flux rope position
on the solar surface to be close to the dimming regions. We conclude that the
expanding flanks of the CME most likely drive and shape the coronal wave.
