The long-term goal of combining virtual reality and the Internet is to create networked multi-user simulations of virtual environments. The Virtual Reality Modeling Language (VRML) represents a limited but significant step towards this goal by creating a standard data file format for representing 3D scene information, together with hyper-link information for associating it with other types of Web documents. Current proposals for extending VRML-1.0 to add behaviors will bring this goal closer, but much work remains to be done. This chapter gives a brief summary of VRML and then describes two significant projects currently under development based on i3D, a high-performance VRML browser developed by one of the authors. The first of these, currently being used at the European Laboratory for Particle Physics (CERN), uses an annotated virtual environment to visualize and walk through the physical design of the new Lepton-Hadron Collider (LHC) before it is built. The second project, Virtual Sardinia, allows the user to tour a 3D terrain visualization of the island and access historic and tourist information through hyper-links.
