HOLY wells had both material and spiritual importance to our ancestors. Material because they provided an unlimited source of fresh water. Spiritual importance because they were often attributed with miraculous healing qualities, the power to grant wishes or other properties.
Most holy wells are not wells as we know the word today. They are springs of water coming out of the ground. Often they would have stone structures built around them (mostly these have fallen into disrepair). Sometimes offerings (coins, hankies etc) were left around the well as an offering to the spirit that was believed to possess the well.
Most of the wells were used well into the 20th Century and in the 1980s Mark Valentine formed a research group to log and on occasion restore these wells before they were lost for good. His group is no longer active but back issues of his journal are online.