One of the basic activities of HHI is construction, production, publishing and maintenance of charts in analogue format (paper charts) and digital format (ENC). Nautical chart is a representation of a particular navigation area with the main purpose to ensure safe navigation of ships. They are constructed in Mercator projection at different scales depending on navigational purposes. HHI chart production includes:
- Overview charts – Adriatic Sea, Ionian Sea, and other parts of the Mediterranean Sea
- General charts – Adriatic Sea and a part of the Ionian Sea
- Coastal charts – Eastern Adriatic Sea
- Approach charts – parts of Eastern Adriatic Sea
- Harbour charts – major Eastern Adriatic ports, harbours, anchorages, and channels
- Berthing charts – major ports and harbours in the Croatian part of Eastern Adriatic
- Thematic charts - special charts to be used with Nautical charts
- Other nautical charts