Smithsonian trinomial facts for kids
Smithsonian trinomials are special codes used to name archaeological sites in many parts of the United States. These codes help archaeologists keep track of places where old things like tools, pottery, or ancient buildings are found.
Each code is usually made up of three parts:
- One or two numbers for the state.
- Two letters for the county (or a similar area) within that state.
- One or more numbers in order, showing when the site was listed in that county.
The Smithsonian Institution first created this system in the 1930s and 1940s. Back then, the 48 states were given numbers in alphabetical order. When Alaska became a state, it got number 49, and Hawaii got number 50. Washington D.C. and other U.S. territories do not use these numbers. Today, each state is in charge of giving out its own trinomial codes.
Most states use a code like "nnAAnnnn" (for example, "1AAnnnn" for Alabama). But some states add a space or a dash, like "nn AA nnnn" or "nn-AA-nnnn". Some states also have their own unique ways of using the system. For example:
- States like Arizona, California, Connecticut, Maine, Rhode Island, and Vermont use short two-letter names for their state instead of the Smithsonian number.
- Alaska uses three-letter codes from special maps (USGS map quadrangles) instead of county codes.
- Hawaii uses a four-part code that includes a number for the island and a number for a map section, along with the state number and site number.
- Connecticut and Rhode Island don't use county codes at all; their site codes are just the state abbreviation and a number for the whole state.
How States Label Ancient Sites
Here's a look at how different states use codes to identify archaeological sites:
State | Format | County or equivalent codes |
---|---|---|
Alabama | 1AAnnnn | AA: Alabama County Abbreviation for Archaeological Site Number Designation |
Alaska | 49‑AAA‑nnnn | AAA: Alaska Quad Map |
Arizona | AZ AA:nn:nn(XXX) | AA:nn: Arizona Quad Names and Numbers |
Arkansas | 3AAnnnn | List of counties in Arkansas |
California | CA‑AAA‑nnnn | AAA: California Counties and their Abbreviations |
Colorado | 5AAnnnn | List of counties in Colorado |
Connecticut | CT‑nnnnn | No county code; state abbreviation and a sequential number only |
Delaware | 7ABnnnn | A: K = Kent County, N = New Castle County, and S = Sussex County. B: Figure 25: Map of blocks |
Florida | 8AAnnnn | List of counties in Florida |
Georgia | 9AAnnnn | AA: County Abbreviation Codes |
Hawaii | 50‑nn[1]‑nn‑nnnn | nn[1]: 10 = Hawaii, 20 = Kaho'olawi, 30 = Kaua'i, 40 = Lana'i, 50 = Maui, 60 = Moloka'i, 80 = O'ahu, 91 = Necker, 92 = Nihoa |
Idaho | 10AAnnnn | |
Illinois | 11AAnnnn | List of counties in Illinois |
Indiana | 12AAnnnn | List of counties in Indiana |
Iowa | 13AAnnnn | AA: Iowa County Abbreviations for Site Designation |
Kansas | 14AAnnnn | AA: Kansas County Abbreviations for Archeological Trinomials |
Kentucky | 15AAnnnn | List of counties in Kentucky |
Louisiana | 16AAnnnn | List of parishes in Louisiana |
Maine | ME-nn-nn | |
Maryland | 18AAnnnn | List of counties in Maryland |
Massachusetts | 19-AA-nnnn | |
Michigan | 20AAnnnn | List of counties in Michigan |
Minnesota | 21AAnnnn | AA: Trinomial Site Designations for MN Counties |
Mississippi | 22‑AA‑nnnn | List of counties in Mississippi |
Missouri | 23AAnnnn | List of counties in Missouri |
Montana | 24AAnnnn | |
Nebraska | 25AAnnnn | |
Nevada | 26AAnnnn | |
New Hampshire | 27‑AA‑nnnn | AA: Belknap (BK) · Carroll (CA) · Cheshire (CH) · Coos (CO) · Grafton (GR) · Hillsborough (HB) · Merrimack (MR) · Rockingham (RK) · Strafford (ST) · Sullivan (SU) |
New Jersey | 28AAnnnn | |
New Mexico | 29AAnnnn | |
North Carolina | 31AAnnnn | AA: Alamance (AM) · Alexander (AX) · Alleghany (AL) · Anson (AN) · Ashe (AH) · Avery (Av) · Beaufort (BF) · Bertie (BR) · Bladen (BL) · Brunswick (BW) · Buncombe (BN) · Burke (BK) · Cabarrus (CA) · Caldwell (CW) · Camden (CM) · Carteret (CR) · Caswell (CS) · Catawba (CT) · Chatham (CH) · Cherokee (CE) · Chowan (CO) · Clay (CY) · Cleveland (CL) · Columbus (CB) · Craven (CV) · Cumberland (CD) · Currituck (CK) · Dare (DR) · Davidson (DV) · Davie (DE) · Duplin (DP) · Durham (DH) · Edgecombe (ED) · Forsyth (FY) · Franklin (FK) · Gaston (GS) · Gates (GA) · Graham (GH) · Granville (GV) · Greene (GR) · Guilford (GF) · Halifax (HX) · Harnett (HT) · Haywood (HW) · Henderson (HN) · Hertford (HF) · Hoke (HK) · Hyde (HY) · Iredell (ID) · Jackson (JK) · Johnston (JT) · Jones (JN) · Lee (LE) · Lenoir (LR) · Lincoln (LN) · Macon (MA) · Madison (MD) · Martin (MT) · McDowell (MC) · Mecklenburg (MK) · Mitchell (ML) · Montgomery (MG) · Moore (MR) · Nash (NS) · New Hanover (NH) · Northampton (NP) · Onslow (ON) · Orange · Pamlico (PM) · Pasquotank (PK) · Pender (PD) · Perquimans (PQ) · Person (PR) · Pitt (PT) · Polk (PL) · Randolph (RD) · Richmond (RH) · Robeson (RB) · Rockingham (RK) · Rowan (RW) · Rutherford (RF) · Sampson (SP) · Scotland (SC) · Stanly (ST) · Stokes (SK) · Surry (SR) · Swain (SW) · Transylvania (TV) · Tyrrell (TY) · Union (UN) · Vance (VN) · Wake (WA) · Warren (WR) · Washington (WH) · Watauga (WT) · Wayne (WY) · Wilkes (WK) · Wilson (WL) · Yadkin (YD) · Yancey (YC) |
North Dakota | 32AAnnnn | AA: NDCRS Site Form Training Manual - Section I: Site Identification - County Codes (Page 10) |
Ohio | 33‑AA‑nnnn | AA: Appendix B: County Codes (OAI Codes) (Page 61) |
Oregon | 35‑AA‑nnnn | List of counties in Oregon |
Pennsylvania | 36‑AA‑nnnn | List of counties in Pennsylvania |
Rhode Island | RI‑nnnn | No county code; state abbreviation and a sequential number only |
South Carolina | 38‑AA‑nnnn | List of counties in South Carolina |
South Dakota | 39AAnnnn | |
Tennessee | 40AAnnnn | AA: County Abbreviations for Archaeological Site Numbers |
Texas | 41‑AA‑nnnn | AA: Texas County Abbreviations |
Utah | 42‑AA‑nnnn | List of counties in Utah |
Vermont | VT‑AA‑nnnn | AA: Addison (AD) · Bennington (BE) · Caledonia (CA) · Chittenden (CH) · Essex (ES) · Franklin (FR) · Grand Isle (GI) · Lamoille (LA) · Orange · Orleans (OL) · Rutland (RU) · Washington (WA) · Windham (WD) · Windsor (WN) |
Virginia | 44-AA-nnnn | |
Washington | 45‑AA‑nnnn | List of counties in Washington |
West Virginia | 46‑AA‑nnnn | List of counties in West Virginia |
Wisconsin | 47‑AA‑nnnn | List of counties in Wisconsin |
Wyoming | 48AAnnnn | List of counties in Wyoming and also YE for sites within Yellowstone National Park |