It's where the grain is stored. They also come in a round version. This is in North-West Spain between Leon and Burgos in the last week of June. It's an amazing place - heavy skies and yellow fields for miles. And thank you very much for your kind comment.

I love Spain (and I'm bilingual in Spanish). I was in Pamplona last year (a month *after* the running of the bulls) and wanted to stay for a week's vacation, but had to get back to work. I'll try again.