THE PALACE
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om the central arch to each flanking tower of the alace; it has been conjectured that the main entral arch and flanking windows were repeated at ach end of the colonnade, next to the angle towers. In any case the whole of this cryptoporticus must ave made a most imposing show from the sea.
  The interior of the building was laid out on the ines of a castrum or Roman fortified camp; that is to say, it was divided into four quarters, intersected at right angles by two straight roads. It bad three main gates besides the entrance from the sea-front. Of these gates the Porta Aurea, on the north side towards Salona, is in fairly good preservation, with its beautiful arcading, brackets and niches. On the west side the Porta Ferrea is still an interesting relic of the palace, giving access to the market-place of the new town through a vista of picturesque arches; its opposite gate, the Porta Argentea or Aenea, has disappeared ; it was known in the Middle Ages as the Porta Nuova, and lllls V enetian lion over the lintel. Outside the ^ orta Argentea is the great market of Spalato. Each angle of the palace had a massive square *r,'A er> and each of the three gates were flanked by l)(tagonal towers. Between each angle tower and ft<lte tower was a smaller square tower breaking