Mill Brook Preserve South Trail Head — Mill Brook is notable for the largest annual migration of alewife fish from Casco Bay to Highland Lake. The fish migration can be seen while hiking along the trail in late May and early June. This secluded and hilly forest valley is peaceful and feels remote while just minutes from Maine’s largest urban center. This preserve is in the homeland of the Wabanaki People. We respectfully acknowledge these People of the Dawn — past, present and future — and their connection to these lands and waters. When we went last year, it was...