In solid mechanics, there is considerable interest in achieving “invisibility”. The applications in mechanics include protection of structures and parts of structures from potentially harmful transient waves and steady state vibrations. A suggested large scale application is that protection against seismic waves from earthquakes could be achieved by using cloaking to re-route the waves around sensitive infrastructure. The construction of mechanical cloaks requires fine-tuning of the elastic properties of the cloaking, so-called metamaterials.