A new modern integrated sea-level monitoring system has been installed at Alexandria. New precise hourly tide, GPS, and metrological observations have been collected, processed, and analyzed for the years 2001, 2002, and 2003. Additionally monthly and annual tide records of a number of tide gauge stations in Egypt have been collected and investigated. Accordingly, tidal variations over the twentieth century have been explored in order to describe the sea-level rise phenomena and achieve an accurate recent re-definition of the national geodetic vertical datum of Egypt. This research illustrates the heterogeneous data sources, discusses the developed processing procedures, and presents the obtained results.