Argiope trifasciata

Banded Garden Spider - most active from mid-summer to first frost. The female can produce painful bites to humans when threatened. The eggs overwinter and hatch in the spring. It can be found in certain areas of Europe, namely the Iberian Peninsula, the Canary Islands, and Madeira, as well as in North America. I came across this one along the banks of the salt pans at Cabanas De Tavira in Portugal during October.