As I have no deep rooted Welsh ancestry I explored the site using the origins of a Welsh-born friend. I've traced his origins back to the village of Pentyrch in Glamorganshire. Searching Pentyrch on the site gave 13 hits. The Iron Age bronze terret with red enamel inlay, shown here, has a caption which informs it would have guided the reins of a chariot drawn by two ponies, and was found near Pentyrch in the 1960s.Of particular interest to me was an image of a page from a 1824 land use survey (terrier) of the Glamorgan estates of the Marquess of Bute. There is a land lease to Thomas Jenkins, the same name as my friend's earliest known ancestor. It documents a three lives lease of 81 acres of land at a rent of seven pounds and sixpence. The lease commenced in 1764 and two of three people whose lives are mentioned are still alive in 1824, ages 66 and 64. They would have been four and six when the lease started. When the last of them died the lease would end.
The value of a three lives lease in its later stages is well illustrated. Whereas Thomas Jenkins benefits from 11.6 acres for each pound of rent the adjacent entries on the page get only 3.3 and 2.3 acres for an "at will" lease. The trick at the start of the three lives lease, assuming you negotiated a good deal, was to choose people who would live to a ripe old age so you, or likely your descendant, would benefit as long as possible.