A common concern of the real−time terrain visualisation of today is the lack of geometric detail, when the terrain model is studied close enough. This is primary not a problem of the digital terrain data used being of too low resolution. The real reason is that the terrain model is pre−generated and stored, thus imposing database size and retrieval rate limitations to the model. The present paper introduces an alternative technique, with which most geometric detail is created only when needed (procedural geometry). This renders many important benefits, including unlimited detail, no repetition of geometry, and optimal system resources usage. An implementation of the procedural geometry technique, Blueberry3D, is presented, illustrating examples of the kinds of geometric detail that allows itself to be procedurally generated. Background Most real−time terrain visualisation packages of today rely on a simple concept. An orthographic aerial photo or satellite image is draped upon a ...