Study of ancient rocky shores is an area of study much neglected by geologists and paleontologists, because it is widely believed fossil rocky shores are poorly preserved in the geological record. Recent years have show a modest increase in the number of published articles in which ancient rocky shores are reported. Examples now are known from nearly all geologic time periods. Although original and present exposure are limited factors, many unconformities are untapped sources of primary data on ancient rocky shores. Data have been slow to accumulate because unconformities typically are seen in cross section, the scale of observation applied often is too coarse, and the general field geologist is unaware of what kinds of data are useful.