In addition to the domes, vaults, and arches, and the Roman building methods used to create them, the missions inherited several architectural features from mother Spain. One of the most important design elements of a mission was its church belfry, of which there were four distinct types: the basic belfry, the "espadaña", the "campanile", and the "campanario". The basic belfry was merely a bell hanging from a beam which was supported by two upright posts. The belfry usually stood just to one side of the main entrance to the church. The second type, the "espadaña", was a raised gable at the end of a church building, usually curved and decorated; it did not always contain bells, however, but was sometimes added to the building simply to give it a more impressive facade. The "campanile", probably the most well-known bell support, was a large tower which held one or more bells; these were usually domed structures, and some even had lanterns atop them. The final method for hanging bells is the "campanario", which consists of a wall with openings for the bells. Most walls were attached to the sanctuary building, save for the one at the Pala Asistencia which is a standalone structure. The "campanario" is unique in that it is native to Alta California.