often built on the foundations of older norman churches, the perpendicular gothic-style somerset towers became landmarks for travelers, with their square, corner-buttressed towers typically positioned on the west side of the churches. the towers soar more than in some cases – in the case of wells cathedral's north tower (1440). most of the towers house bells, and bell-ringing became a tradition still practiced in some of these english country churches. most of the churches in this article have been designated, under the planning (listed buildings and conservation areas) act 1990, by english heritage as grade i listed buildings, which is defined as encompassing those "of outstanding or national architectural or historic interest". those that do not achieve grade i are listed as ii*, which means "particularly significant buildings of more than local interest."