Composite volcanoes, also known as strato-volcanoes are steep, symmetrical cones that are made of lava flows, volcanic ash, cinders and other material. Some examples of composite volcanoes is the Mount Fuji of Japan, Mount Cotopaxi in Ecuador, Mount Hood in Oregon, Mount Rainier and Mount St. Helens in Washington.
Composite volcanoes usually have vents at the summit point n which lava flows out. Lava also flows out the cone's fractured sizes and fissures that when cooled, will reinforce the breaches of the cone and ultimately strengthen the structure.
On the interior of the composite volcano is a system of "pipes" and conduits in which lava flows to the sides and the summit of the cone. Through this system, the cone builds in size and strength, as the lava flowing out onto the exterior of the cone slowly accrues and accumulates. Eventually, when the volcano is no longer active, the cone falls apart as the interior becomes exposed. This too rots away to erosion and all that is left in the end is a plug and a dike system that projects above the surface.