This paper discusses the development 3D Web-GIS application using Open Standards and
Open Source software environment. 3D Web-GIS can provide realistic visualization of
spatial information and has immense potential in infrastructure management (life-line
and network infrastructure), disaster management and geological modeling. In our
previous attempts at developing 3D Web-GIS applications, we have experimented with
Java 3D client (Tsunami Geospatial Information Sharing) and also VRML1.0 (Virtual
Reality Modeling Language Version 1.0). However Java 3D Client and VRML1.0
technologies have limitations such as a) proprietary solution not compliant to Open
Standards b) outdated data format (VRML1.0) that is not amenable to handling large
spatial datasets c) lack of integration between 2D Web-GIS clients and 3D geospatial
visualization tools. Several of these limitations can be largely overcome by adopting
recently emerging technologies such as X3D (ISO standard for real-time 3D computer
graphics).  In this study, the X3D functionality have been integrated into a 3D
Web-GIS prototype system The prototype system has been tested for terrain
visualization using medium resolution DEM for parts of Japan. The prototype system is
currently being further improved to enable display of geological bore-hole data and
also for realistic terrain visualization by combining high resolution digital
elevation data and satellite images.