Architectural visualisation has been developing over the year to improve the representation buildings and their contexts to the public. It achieved a long journey from manual drawings to photography to digital 2D and 3D representation, until it reached the era of extended realities (XR), which allowed unprecedented immersive and interactive engagement. Extended reality applications represent a unique opportunity for the visualisation of heritage buildings on many stages; from the early design phase, through the construction and facility management phases, to the education and cultural tourism applications. This paper aims to explore the wide range of state of the art XR applications, investigate their aspects and variations, and study their potentials, challenges and limitations for the built heritage sector.