Since ancient times mathematicians and geometricians have used visualisations to describe, discuss, study and teach mathematics. In mathematics education, visualisations are still used whenever possible to support teaching, to inspire students and feed their need to actually see abstract mathematical facts. In our times, virtual reality presents a fascinating, extremely motivating new tool in teachers' hands which allows students to see mathematics in three dimensions. This article gives an overview of various, mainly immersive, virtual environments that have been developed in the previous 10 years to support mathematics and geometry education. The focus lies on one advanced application for geometry education that has been used and evaluated with over 500 students throughout the years. Findings and teaching experiences are described and discussed.