The role of information and communication technologies (ICT) in education is well recognised--learning environments where the ICT features included are being proposed for many years now. The Web Geometry Laboratory (WGL) innovates in proposing a blended learning, collaborative and adaptive learning Web-environment for geometry. It integrates a well-known dynamic geometry system providing an adaptive environment where face-to-face activities can be combined with computer-mediated activities, in a collaborative or stand-alone, synchronous or asynchronous, classroom or homework way. The WGL collaborative environment allows each student to capitalise on one another's resources and skills. Its adaptive module gives to each teacher the ability to assess the geometric level of each student, allowing the teacher to build the individual profile and/or learning paths. In this paper we begin describing what are the goals that support the development of such an environment, the goals that support our beliefs in the usefulness of such an environment for the teaching and learning of geometry, after which we describe the environment and the case studies already conducted.