building materials, and many kinds of timber. These could not easily be
exploited. Not all of them were effectively investigated in antiquity.
Successful exploitation required cooperation between technical special-
ists, who did not necessarily share a common language. This challenge
explains why surviving historical narratives often contain a good deal of
inter-community tension.
Materials used in the construction of the built environment tradition-
ally composed, throughout prehistoric times, of clay, dry stone, and
wood; from thefifth centurybconwards these came to include ashlar
masonry, cut from granite, marble, limestone, or other, more restricted
rocks, and (from the second half of the fourth centurybc)fired bricks
were used in eastern parts of the region.^6 The higher humidity and
precipitation of northern areas favoured herds of horses and cattle, as
well as sheep and goats, and therefore their respective by-products,
particularly leather and wool. Whereas wool was also produced farther
south, the greater availability of leather goods (for military and civilian
purposes), and of meadows for horse-rearing, gave the northern margins
of the Aegean important strategic advantages.
The mountains and river systems of the region have been subjected to
phases of uplift, faulting and erosion since the Mesozoic era, with the
formation (between 250 million and 65 million years ago) of intermedi-
ate lakes and rivers, creating varied and well-resourced local ecologies.
The region lies within a geologically active zone, close to the interface
between three tectonic plates: the Anatolian, the Eurasian, and the
Aegean Sea plates, whose intersection overlies the Hellespontine Straits
and runs south of two of the chief north Aegean islands, Thasos and
Samothrace. The dynamic nature of the physical landscape has been
reinforced by anthropogenic activity, in the form of forest clearance (for
agriculture, mining and metallurgical processing, and route ways). These
human activities have in turn generated levels of instability in the
physical environment. They have induced changes in the surface pat-
terning of the modern landscape, whose outward appearance (including
urban conurbations, transportation networks, and other contemporary
forms of intensive land use) partly conceals the earlier activities that
characterized the region in classical antiquity. Alluvial sediments have
left a thick layer of clays, gravels, and sand in the middle reaches of river
valleys, particularlyflanking large rivers with strong seasonal dynamic
patterns, such as the Haliakmon, Loudias, Axios, Strymon, Iskur and
Hebros, which have cut sinuous channels through lower-lying terrain
(^6) Fired bricks: Archibald 1998, 291–3.
132 Thelongue duréein the north Aegean