GPS Maps Online
GPS maps are the keys that unlock the potential of GPS receivers. On its own, a GPS receiver will be able to tell you the precise coordinates of where you are, but without corresponding mapping software it cannot tell you much more. At the end of the day, knowing only that you are sitting at 63'10' longitude and 26'16'latitude is not going to help you all that much at all!
Regardless of whether they are portable or fixed, the majority of GPS systems will have certain base maps stored in their memories. Standard maps with handheld units and GPS watches will usually be far less detailed than those that are stored in the memories of marine and in-vehicle systems. This is primarily due to the fact that portable models have less hard-drive storage space than fixed models. That said however, all base maps generally lack detail. In order to get the most out of your GPS system it is therefore advisable to either purchase additional mapping software, create your own maps or download maps from the Internet should your system permit it.
Leading manufactures such as Garmin, Magellan and Lowrance all sell advanced digital base maps which contain far more detail than ordinary base maps. GPS digital maps are divided into three major categories: street maps, world maps and topographical maps. Street maps provide detailed information on roads, recreation areas and off road areas. They are generally designed for use by drivers, so if you plan to use a street map to guide you on a walking tour of an unfamiliar city or town, beware! The route suggested by the receiver is likely to contain no pedestrian pavements or crossings and may therefore be rather tricky to navigate on foot.
World maps contain basic information on cities, towns, highways, railways, rivers and lakes. Although Europe, North America and most developed countries are usually well mapped, maps of Latin America and developing countries are usually far sparser and often lack essential details. Similarly some topographic maps will be filled to the brim with landmarks, points of interest and topographical information while others will sorely lack detail. Strangely enough, the topographic map of the popular Grand Canyon National Parks area is an example of a map which lacks significant details.
Garmin currently manufacture the most comprehensive maps of US Parks which can be purchased for between $80 and $100. Other Garmin Mapsource and Metroguide software packages can be purchased for between $70 and $140 depending on what you are after. You can expect to pay a similar amount for Lowrance Mapcreate , Magellan Mapsend and Magellan Directroute mapping software. Because of their detail, street maps are generally the most expensive. They also take up the most memory, with many portable units only being able to hold one or two detailed street maps at a time.
If you are proficient at using a GPS system, it is possible to create your own maps using specific waypoints and routes. If you use a Garmin GPS system, programs such as MapDekode will allow you to use your own routes and waypoints to create maps using un-encrypted Garmin Mapsource files. Similar programs have also been developed for other GPS brands. It is also possible to download detailed maps from the Internet. Sites such as travelbygps allow GPS users to download maps for free. These maps can then be loaded onto GPS receivers, or in the case of PDA and Laptop GPS systems be used instantaneously.