A superior show is Time Team, produced in England and almost exclusively involved in the British isles.  It is a 3-day 'salvage' format of sites ranging from the Neolithic, Iron Age, Roman, Medieval, Tudor, and other periods.  In Detroit, we get it through TVO Ontario cable.  The show has been on for a number of years beginning in the 1990's.  I only came upon it last year, but I try to catch every one of them.