All through these centuries, nevertheless, barrow-burial had persisted. Nay, more, the barrows were often collected in groups, representing the prototypes of our modern cemeteries. The classic example of such clusters is seen in the barrows around Stonehenge; within a circuit of three miles it is said that there are about three hundred barrows[641]. Another illuminating record is that of the collection of barrows known as the Danes’ Graves, near Kilham, on the Wolds of Yorkshire. Not fewer than 500 graves once existed here, “massed together as in a modern churchyard, not isolated as in the Bronze period[642].” Mr J. R. Mortimer found that the burial-mounds of East Yorkshire fell readily into clusters, some of which contained so many as thirty or more individual barrows. From Mr Mortimer’s conclusion that the ground-plans of these groups agree with the outlines of certain of the heavenly constellations, notably with that of Charles’s Wain, we must, however, withhold assent. The Stonehenge barrows are grouped, not actually “massed.” Other groups of tumuli might be given; we will merely mention those interesting cases where one or two large barrows are connected with collections of tiny mounds; the smaller ones, perhaps, representing the resting-place of the poorer tribesmen[643]. It would be safe to assert that most of the small barrows have ere now been long levelled down. Of the larger mounds not a tithe of the original number remains. The clusters of barrows, one may consider, led indirectly to the Christian cemeteries. At first, as stated in a sermon by St Chrysostom (A.D. 403), the Christian communities had their cemeteries outside the walls of cities[644]. Interment in churchyards was not a primitive practice, and was prohibited by the decrees of early church councils. The custom gradually crept into use about the sixth century[645], the innovation appearing first in connection with monastic settlements. By the time of St Cuthbert (_c._ A.D. 742) the practice was becoming well known, the bones of pious men and martyrs being actually admitted within the building itself[646]. To such an extent did the practice grow, that the floors of churches often became too uneven for walking over. As a parenthesis, we note that the early ban against churchyard burial must not be interpreted as contradicting the probability of the building of churches near older Christian cemeteries.