Bivouac.com Chapter Home Help Index Login
Different Map Views (35) Top Level
First, some tricky terminology to distinguish between "Map Views" and "base maps". A "map view" (or "display choice") is a program choice in GMap. For example, GMap has a drop down menu which has about 14 map views such as "t2 - MyTopo". A "basemap" is a set of data. For example, the whole set of 1:50K maps in Canada is a "basemap", and the 1:250,000 maps are another basemap. A map view can use different basemaps depending on the location and the zoom level. For example, the "t4 CalTopo High-res USA" will display the 1:20,000 TRIM maps when in British Columbia, but USGS basemaps when in USA.
In this tutorial, my objective is to introduce the most useful map views in GMap. Click the black drop down arrow at the extreme right edge and you should see a list of basemap choices such as below: (I'm only showing the choices I regularly use).
h Hybrid satellite shows labelled logging roads
t2 MyTopo best artwork and matches GPS
t4 Caltopo (BC Trim data,for logging roads and peak heights
t5 Topo Canada - has good contour labels
t8 Topo OSM Cycle World - shows trails
- h - Aerial Google Hybrid
This is one of the most useful displays in GMap, more useful than the plain Satellite maps because roads and peaks are labelled. If you zoom in to 100m scale, you see road labels. These are often pretty good names for the roads, although sometimes they will label a whole set of forks with the same name.
- t2 MyTopo
This is the default display for Bivouac. In all Canadian provinces it displays scans of the familiar 1:50K National Topographic Series (NTS) paper maps. These are some of the best maps ever made, and have the most suitable contour interval and coloring for Canadian mountaineering. The contour interval for many areas is still 100' contours, and in some areas 40m contours. One flaw is that the contour lines are very sparsely labelled making it difficult to determine the elevation of a given point. The "t5 Topo Canada" labels are much more useful, and I often briefly flip to this view when getting elevations for road waypoints.
- t4 CalTopo
Despite the GMap label "USA", the most important use of this display is in British Columbia, where it shows the 1:20,000 TRIM data. This data is more accurate and newer than the old 1:50K maps. It shows calculated spot heights of many more mountains. It shows a vast network of logging roads as dotted maroon lines. Most of these are overgrown or irrelevant, but the display is still useful for digitizing when the satellite view is too dark to see.
When in USA Caltopo shows the USGS maps, and high resolution. Eg: Go to Mount Mckinley and switch between CalTopo and MyTopo. You see that the CalTopo is the same map but much higher resolution.
- t5 Topo Canada
This display shows Tiles from a modernized version of the old NTS 1:50K maps. The government produced these by scanning the old 1:50K maps with some sort of program that recognized the contour lines. So the contour lines are just the same old ones on the 1:50K maps, but clearer. Most useful is that the contour labels are generated automatically and much more frequent than on scans of the old paper maps. I always use this display when trying to fill in elevations for road waypoints. For lakes, rivers and streams it uses the 1:20K TRIM data rather than the old creeks shown on the 1:50K. The TRIM has many more streams than the old 1:50K although some are insigificant.
- t8 Topo OSM Cycle World
Despite the misleading word "cycle" these maps are often very useful for locating trails not in bivouac. For example, if you go to Mount Seymour and zoom in to 100m, you'll see a vast network of trails shown as maroon dotted lines. Many of these have trail labels. These trail networks tend to be best in popular areas near large cities. In more remote areas there will be nothing. And in areas such as around Mount Macdonald on Vancouver Island, they show a vast network of trails and some don't exist at all. Unlike the Bivouac trails, you can't click on them to see any information, or to see where the source of waypoints came from.