424 
SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
particular settlement is also of unusual interest in that, after it had fallen into 
disuse, it was partly overlaid by a smaller settlement formed by two banks. 
A single ring-groove house survives in the remains of the earlier and larger settle 
ment, while three of a variety of ring-ditch houses are visible on the surface 
of the ground in the smaller and later settlement. 
The very few excavations which have so far been carried out among all 
timber enclosures and houses of the types described have shown that they 
represent early settlements of the local Iron Age, which may date at least 
from the 3rd century B.C., if indeed not earlier. Much more remains to be done 
upon them, both to elucidate the great varieties in structural form which occur 
among them, and to determine a more elaborate and intimate pattern of 
dating. It is already apparent that they represent a phase of widespread settle 
ment, the existence of which had not previously been established. 
They constitute by far the largest and the most valuable advance in know 
ledge of the earlier parts of the Iron Age in Britain to have been made in recent 
years. Their survival and discovery have depended equally, on the one hand, 
upon the nature of the ground in which they lie and, on the other, upon the 
expert use of air photographs in the form of stereoscopic pairs at a scale of 
1/10,000. 
A few similar or related structures have been found by other means both 
here and elsewhere. Among these must first be mentioned the few all-timber 
settlements and houses which have been brought to light by chance from be 
neath hill-forts or other evidently secondary settlements in which excavations 
have taken place. Second are a few which have appeared as crop-markings on 
air photographs of one kind or another. The former class have, of course been 
seriously mutilated by the dwellings and other works of the later occupants of 
the sites, while the latter have been shaved so nearly to oblivion by the action 
of the plough that little but the bottoms of ditches and post-holes survive, 
and the occupation levels have been swept away. 
At present, only a few unspoiled examples have been recorded outside the 
areas covered by the Royal Commission on the Ancient and Historical Monu 
ments of Scotland, some of them in adjacent Northumberland and at least 
one in Wales. It is more than probable, however, that many additional exam 
ples will eventually be recorded before afforestation or other perils destroy 
them; and that as threatened examples are excavated, a whole new body of 
evidence about the Early Iron Age in Britain will emerge.