Clue 1: A piece of china

A. While playing on the farmland, four kids found the first solid clue -- a piece of glazed white china with blue decorations. This particular pattern, depicting a Chinese pagoda, was popular in Europe in the mid-1700s.

B. About a dozen years later, archaeologist Doug Birk found a piece that exactly fit the first.

C. and D. Exploration revealed two more pieces, which also were long buried. The pieces of glazed pottery suggest that fur traders had a fort on the site about 250 years ago because some of the leader's dishes came from Europe.

-- Source: Institute for Minnesota Archaeology

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