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The surface of Ganymede has undergone massive re-surfacing and is dominated by the presence of large white ice-belts which have cut older dark terrain into a series of polygonal blocks. Associated with these belts, termed sulci, are numerous linear and curvi-linear structures called grooves. These features are dominant in the re-surfaced material and show intricate surficial patterns. The sulci were formed in a number of phases of extensional tectonic activity and show complex cross-cutting and overlapping relationships. Two computer mosaics were constructed and used to map the geology and structures on an area of Ganymede covered by the Voyager 2 spacecraft imagery. Six terrain units and two major structural groups were classified and sub-divided into 23 structure/terrain groups. A series of solid geology maps and structure maps were produced. The chronological sequence of terrain formation was derived using cross-cutting relationships and crater statistics from the literature. A tectonic model was proposed to explain sulci formation based on comparisons with an Earth extensional rift analogue and crater deformation studies. Models were proposed to explain groove formation and these were compared with theoretical and Earth analogues. Results indicate that the grooves formed at the end of sulci formation within the extensional stress-regime but minor late stage compression has formed grooves with positive relief in localized areas. Frequency/orientation plots of the 23 structure/terrain groups were analysed and used, together with an extended model describing multi cross-cutting sulci, to determine the sequence of sulci and terrain formation. Seven episodes of sulci formation were identified each with a particular age related trend, with three of these the result of major planet-wide activity. These data were then used to derive the tectonic history of this moon.