Základní topografická mapa České republiky 1 : 250 000 v ETRS89

The Base Topographic Map of the Czech Republic 1:250 000 in the plane coordinate system of the European Terrestrial Reference System 1989 in the Universal Transverse Mercator projection of meridian zones (ETRS89-TMzn), hereinafter referred to as ZTM 250/ETRS89, is a fundamental national map series. ZTM 250/ETRS89 extends the scale series of the national map series from 1 July 2023 with a variant of ZTM 250 in the plane coordinate system ETRS89-TMzn, as an alternative to ZTM 250 in the national coordinate system S-JTSK. In terms of content, ZTM 250/ETRS89 does not differ from the primary ZTM 250/S-JTSK. ZTM 250/ETRS89 covers the entire territory of the Czech Republic in a continuous map layout; the territory of the Czech Republic is shown on 12 map sheets. The sheet lines of the layout (inner frames) of the ZTM/ETRS89 map sheets form images of meridians and parallels at a specified spacing dependent on the map scale. A ZTM 250/ETRS89 map sheet thus covers an area of 1° × 2° (latitude × longitude). The dimensions do not include the accompanying elements shown on the printed version of the map sheet (i.e. the boundary band and frame and non-frame data). The dimensions of the printed map including all frame and non-frame data are 550 mm × 800 mm. ZTM 250/ETRS89 map sheets are identified by a nomenclature of alphanumeric character derived from the designation of the International Map of the World 1:1 000 000 (NM-33 and NM-34 for the Czech Republic), covering 6 degrees of longitude and 4 degrees of latitude. Additional characters specify the position of the map sheet of a given scale within the map sheet of the smaller scale from which it is derived. The map sheets are further supplemented by a map sheet name, which is generally identical to the name of the largest settlement on the given map sheet. ZTM 250/ETRS89 map sheets are created by dividing a map sheet of the International Map of the World 1:1 000 000 into 12 map sheets using 4 rows of 1 degree of latitude and 3 columns of 2 degrees of longitude, designated consecutively within the International Map of the World map sheet in rows from the north-west map sheet as 01 to 12. An example of a map sheet designation is NM-33-08 Jihlava. ZTM 250/ETRS89 contains planimetry, altimetry and descriptions. The planimetry includes settlements, roads, hydrography, boundaries of administrative units, boundaries of Protected Landscape Areas, vegetation and land surface. The altimetry includes terrain relief shown by contour lines with a basic contour interval of 50 metres, terrain steps, rock features and points with given elevation including their altitude. The map description consists of standardised geographical nomenclature, names of municipalities and parts of municipalities, contour line elevations and points with given elevation, names of districts and protected areas. The printed map sheets also contain the ETRS89-TMzn and S-JTSK one-kilometre map grid and the ETRS89 geographical grid, a map frame with frame data (e.g. descriptions of neighbouring states, affected Protected Landscape Areas and orographic units, coordinates) and non-frame data (e.g. map legend, imprint data, graphical, numerical and slope diagram, interpolation scale of the ETRS89 geographical grid, graphical representation of the map in the map layout, expression of meridian convergence and magnetic declination, etc.). The map is produced by transforming ZTM 250/S-JTSK data, followed by data verification and the addition of frame and non-frame data. The source data for ZTM 250/S-JTSK are the Fundamental Base of Geographic Data of the Czech Republic (ZABAGED®) and the Database of Geographic Names of the Czech Republic Geonames. Only features occurring within the territory of the Czech Republic are shown. When displaying planimetry in ZTM 250, methods of cartographic generalization are applied to ensure graphical clarity — census choice of map elements and normative choice of map elements (omission of elements based on quantitative and qualitative parameters and further reduction of the number of elements where applicable), geometrical generalization (displacement, simplification of shapes and merging of areas) and reclassification (grouping of multiple categories of elements into a single category).