This new map provides contiguous topographic detail over a region approximately 311 miles by 249 miles (500 kilometers by 400 kilometers).
这张新地图给出了附近大约500千米乘400千米范围的地形。
2
Traditional construction methods firstly in the small scale topographic map, choose several feasible options, through field reconnaissance to confirm the optimize region.
传统的机场建设方法是首先在小比例尺地形图上选择几种可行方案，通过实地踏勘确定最佳区域。
3
The complicated topographic features and varied weather bless the Shidian region with advantageous conditions of rich natural resources.