Inland Electronic Navigational Charts (IENC) are specialized digital charts designed for information systems for displaying inland electronic navigational charts (IECDIS). These systems are intended primarily for on-board navigation equipment. IENC maps represent RIS information items according to Section 4 of Decree No. 356/2009 Coll. on information recorded in River Information Services. The map standard is defined according to the current version of the Encoding Guide for Inland Electronic Navigational Charts (Encoding Guide for Inland ENCs). Data sets on the EuRIS API in the form of digital charts also contain international IENCs of partner states that apply selected types of services according to Directive 2005/44/EC of the European Parliament and of the Council on harmonised river information services (RIS) on inland waterways in the Community. Each map sheet on the EuRIS API has its own identifier (mapID) and a name according to the waterway section (name). The link to a clear list of all map sheets on the EuRIS portal is: https://www.eurisportal.eu/enc