2. The demand for aggregates in each geographical part of Scotland varies considerably and is likely to be influenced by demand in areas with high population density where access to suitable local resources is often restricted. Market areas are generally set in relation to the economic viability of transporting the resource. This effectively means that in certain areas, particularly in the Scottish midlands, market areas will extend beyond local authority boundaries whilst in some rural areas local resources will be used in the main to satisfy local needs. The exception to this rule is the coastal quarry at Glensanda in Highland which primarily supplies markets outwith both Scotland and the United Kingdom.