Shrines are built in places where an imam - a person whose life had been lived in exceptional holiness - had died or been buried. People make pilgrimages to these shrines and pray to the imam for assistance with life's difficulties. Promises are made and bound by a strip of cloth or string to the gate surrounding the tomb. Money is tossed onto the tomb as well. One form of these shrines is pre-Islamic, and comprises a location of tall trees and water that is believed to have a special energy. Stone walls were built in these open-air shrines, into which people placed candles and offerings. The trees were considered sacred and could not be cut down. The early Islamic shrines were small, simple buildings with a domed roof. Wealthier shrines may be quite large and decorated inside and out with tiles bearing inscriptions from the Qur'an, gilded walls, and chandeliers.