25 years virtual reconstructions: Current challenges and the comeback of physical models

The virtual reconstruction of the monastery at Cluny [1] from 1989 stood at the beginning of the short history of virtual reconstruction. Although this took place only 25 years ago, design and form of presentation have changed dramatically and the greatest potential of virtual models - digitality - and thus the principal possibility for transforming digital data sets into different forms, was first convincingly realised in recent years through the use of rapid prototyping. Furthermore virtual models have been increasingly established as a tool for research. The following comments deal with previous and future developments, opportunities and challenges and the reflection on more than 20 years of experience [2].