someone asked earlier, i believe....about the differences between the
Garmin III (discontinued) and the III+
http://www.garmin.com/products/gpsIII/americas.html
III III+
Database or Basemap Basemap (details) Basemap- 20 mi (details)
Additional map options N/A MapSource CD-ROM uploadable information
details on the III:
The Americas Land Data basemap includes the United States, Alaska, Canada, Mexico, Central and South America, and covers an area from W180 to W30 Longitude, S60 to N75 Latitude. Also included is a high-level worldwide map with political boundaries and major cities. The best zoom range on the Americas Land Data basemap is the 20 m scale.
The internal basemap is permanent and cannot be updated or upgraded. The standard map coverage for the Americas version includes:
Oceans, rivers and lakes (greater than 30 sq. miles)
Principal cities and a small amount of smaller cities and towns
Major interstates and principal highways
Political boundaries (state and international borders)
United States?In addition to the standard map coverage, it also includes:
Small lakes, major streams and rivers
Principal urban areas (including Alaska and Hawaii)
Railroads
National and State level roads, plus some local roads in or near urban areas
More detailed coastline
Small cities and towns
Alaska?In addition to the standard map coverage, it also includes:
National and State level roads, plus some local roads in or near urban areas
Lakes greater than 5 square miles
Small cities and towns
Railroads
Canada?In addition to the standard map coverage, it also includes:
Lakes greater than 5 square miles (Southern Canada)
Lakes greater than 10 square miles (Central Canada)
Railroads
Mexico, Central and South America:
Standard Map Coverage
---------------------------------------------------
just FYI
hope this helps...