The Global Sea Level Observing System (GLOSS) Group of Experts (GE) data archaeology group is collating tools and producing guidelines for historic sea level data. They aim to aid the discovery, scanning, digitising and quality control of analogue tide gauge charts and sea level ledgers. Their goal is to improve the quality, quantity and availability of long-term sea level data series. This paper examines different tools for the automatic digitisation of tide gauge charts, the methods available for transcribing handwritten tide gauge ledgers and possible future developments that might speed up and partially automate these processes.