The Grand Staircase is remarkably well preserved with four flights of steps and evidence for a fifth at the top. Belonging to the start of the Late Minoan period, the period of "Great Rebuilding", it allows gentle access to some of the best preserved and easily understandable rooms of the Palace. The steps are of gypsum with a columned balustrade descending with them to the Hall of the Colonnades illuminated by its lightwell.