Sea Drive offers coverage of the US including the Great Lakes, US Territories like Guam and Puerto Rico, and inland waterways. We'll expand more globally in the near future.
Electronic navigation charts vary in scale, ranging from 1:4,000 to 1:1,000,000. On one extreme, large scale charts are called berthing charts, while small scale charts are referred to as overview charts. In the map above, Sea Drive shows berthing, harbor, approach, and coastal charts as blue colored, while general and overview charts are purple.