Opus Operandi: A Pool of Clear Water

From the introduction:

The lush farmlands of Paravelly cover an area roughly twenty two miles across and about twenty six long. The gently rolling hills and valleys are home to many farms and a couple of villages. The river Choline wanders sedately from west to east. It is shallow and easily crossed in most places. The land makes good grazing pasture for sheep and cows, and produces a fine crop year after year from the dark soil, mainly of staple foods like carrots and potatoes.