Triangulation Stations

Some of the triangulation stations used in land surveys are included on the Department of Transportation County Maps, which were the source of the Detailed Township Maps.  These are of little interest to most researchers, but in some cases they provide the only surviving clue as to the location of an early settlement.  

If you are searching for a place associated with one of these points, the following observations & tips may help:

  • There is no reason to believe that all Triangulation Stations of this order were included on the maps.  In fact, I have noticed that they are most often shown in areas that are now sparsely populated.
  • When both a Triangulation Station and a Town bearing the same name are shown, they are usually within five miles of each other.  Triangulation Stations were selected for a clear line of sight to nearby stations, so they could be near population centers but not in one.  They were sometimes established in an adjoining Township or even an adjoining County.
  • All stations shown on the DoT maps have been included in the indexes.  Survey dates are not available, so there's no way of knowing whether one is relatively new or was associated with an early settlement.  I have found cases in which a settlement shown on the 1895 or 1915 map was not on later ones, but a Triangulation Station bearing that name appears in the general area on modern maps.  
Want to find even more information about one of these Triangulation Stations? Just consult the topographical maps.  Note the nearest searchable landmark shown on the Detailed Township Map (usually a Town) and its distance and direction from the Triangulation Station.  Use that landmark to find the appropriate topographical map, then center your display near the Triangulation Station and select the most detailed scale -- sometimes, you'll find the named benchmark. Sometimes, just the BM symbol. With luck, though, you'll spot something (perhaps a church or a cemetery) bearing that name within a 5-mile radius.