150722 Park built on Huge trash pile

150722 What's so unusual about this city park near St Paul MN? It's an artificial hill about 80 feet high, 1/4 mile long and nearly as wide.
(see answer in comments).
Comment = It's built entirely of trash from a bunch of decades ago. Today it's a very nice park and you'd never know it's history.  There's a Frisbee course there too.
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150417 a & b (Lochness park in Blaine MN)