The amount of memory required for detail maps depends heavily on how much map data is available for a particular area. Dense metro areas with lots of roads and landmarks take more memory than rural areas with few map features.
Coverage areas are usually broken down into smaller chunks that can easily fit into memory. Maps from Garmin, for example, usually require about 0.5 MB to 3 MB per chunk.
Here are a few samples from Garmin's City Select v6 map product:
Note: Sizes shown are based on 1 MB = 1,048,576 bytes.
GPS receivers with more memory can hold more detail maps. Exact memory requirements depend on the receiver model and map version.
See Also
