Observations of the trail of destruction of the Sumatra tsunami of 26 December 2004 indicate remarkable, small-scale spatial variations, of the order of a few kilometers, of water inundation and destruction in southwestern Sri Lanka <Shiermeier, 2005; Liu et al., 2005> that are much smaller than the tsunami wavelength of ˜100 km. For example, the town of Peraliya, was awash with an approximately 1.5-km water inundation from a wave of 10 m in height; the inundation there carried the passenger train Samudra Devi (the Ocean Queen) inland some 50 m, killing 1700 people.Yet, ˜3 km south, in Hikkaduwa, there was a mere 2―3 m wave height, 50-m inundation and no deaths.