One of the most fundamental aspects of architecture is the arch. The development of the arch permitted architects to open up space while maintaining support. The system works because although stone does not have great tensile strength, the compressive strength and shape of the voussoir within the arch transfers the weight of what it is holding over the open space through the springing to the supports on either side. Each voussoir is cut so that the angles lead to the central stone (or stones) called the keystone (keystones). When it is in place the system is fully functional. The rounded arch is used in earlier arches and is associated with Romanesque architecture as well. The pointed arch is associated with Gothic architecture and is partially responsible for the increased height of those structures. Other architectural aspects derived from the arch include: the triumphal arch, arcade, tunnel vault, and dome.