Bathymetry Netherlands – polygons with area name, type of measurement and date of measurement of coastal and trade lanes 20 mtr

This loding polygons file provides information about the area name, type of measurement and measurement date at the grid of the last gembed heights of the coast and the subdivisions 20 meters instead of Rijkswaterstaat.本加载多边形文件（loading polygons file）提供了沿岸最新gembed高程网格对应的区域名称、测量类型与测量日期信息，其采用20米间隔的细分网格，替代荷兰皇家水利署（Rijkswaterstaat）的相关测量标准。