## Mid-West Map Company

Most MWM maps from 1926 to 1936 contain a code consisting of a mixture of numbers and letters. Dates may be determined from the first digit following the first letter of the code, which is the last digit of the year. There are usually two codes: on the cover, and one on the map inside. Use the later date if they don't agree. For example:

'R0529' (cover), 'Q08CE' (inside) = 1930

'2P8818' (cover), 'O716C' (inside) = 1928

Also, these guidelines may help to date a MWM map:

Maps with text only covers 1926-29; illustrated covers 1930-36

Maps measuring 5" x 7" usually 1926-28; 5¼" x 8¼" are 1927-34

"Highway Map and Guide" title used 1926-33

"Highway Map" title used 1934-36

Date codes were dropped after 1936, but cover and map border styles can be used to pinpoint a date:

### MWM Multiple Advertiser Edition cover styles

1936

1937

1938

1939, 40

1941

### MWM Single-Sponsor Edition cover styles

1937

1938

1939

1940

1941

1937 maps feature little illustrations of various vehicles between the letter & number grid references. This was changed to check marks for 1938-40 maps.

1939-40 date codes start with 'A142...' with next 2 digits the year, reversed:

'A142934210' = 1939

'A14204425' = 1940

1941 dual MWM & Gousha, with Gousha cartography and date codes.

## California State Automobile Association

Some idea of the publication year for early maps that aren't dated can be obtained from the address of their offices in San Francisco:

'681 Market' from 1911-14

'1628 Van Ness' from 1915 to 1925

'150 Van Ness' starting in 1926

Up to 1949, codes are read forward as month-year:

'5-39' = May 1939

'7-48' = July 1948

From approx. 1949 to 1965, codes are read backwards as month, year:

'251' = Jan. 1952

'366' = June 1963

Starting in 1966, codes are read forward as month-year:

'9-67' = Sept. 1967

## Clason Map Company

Clason maps from 1928 to 1931 have codes, but not related to dating the maps.

From 1923 to 1931, map legends can be used to determine years:

"Highly Improved Roads"

"Paved and [Hard] Surfaced Roads" or, if you see only two road classifications

"Through Routes" or "Best Roads"

Graved Roads (or any mention of gravel), plus no roads printed in red

Red roads (Red U.S. Highways appear for the first time and in all subsequent years) along with a mention of gravel and/or macadam roads

All-Weather Roads, plus (Blue) printing

All-Weather Roads, plus (Black) printing

For the "Green Guide" series, cover styles changed over the years as shown below:

## Automobile Club of Southern California

Some idea of the publication year for early maps that aren't dated can be obtained from the address of their offices in Los Angeles:

'758 S. Olive" (or "8th & Olive") prior to 1914

'1344 S. Figueroa' from 1914 to 1923

'Figueroa & Adams' from 1923 to 1927

'2601 S. Figueroa' starting in 1927.

1929 to 1934, codes usually read right to left as month-day-year:

'92717' = July 17, 1929 (each digit right to left)

'29163' = March 16, 1929 (code right to left, sub-components left to right)

'03311' = Jan. 13, 1930 -or- Nov. 3, 1930 (ambiguous, could be either)

1935 to mid-1940s, codes read left to right as month-year:

'6-35' = June 1935

'436' = April 1936

Mid-1940s to 1962, codes read left to right as day-year reversed-month:

'1744' = April 1, 1947

'218412' = Dec. 21, 1948

'1947' = July 1, 1949 (NOT 1947!)

'C-5361' = Jan. 5, 1963 (some codes preceded by 'C-')

Starting 1963 codes read left to right as month-year:

'9-67' = Sept. 1967

["ROAD MAP DATING GUIDE FOR RAND MCNALLY, GOUSHA & GENERAL DRAFTING", "Compiled by Mark Greaves (RMCA #39), Supplement to *The Legend* #96, Summer 2023", "<table><thead><tr><th>YEAR</th><th>R. McN.</th><th>GOUSHA</th><th>GEN. D.</th><th>YEAR</th><th>YEAR</th><th>R. McN.</th><th>GOUSHA</th><th>GEN. D.</th><th>YEAR</th><th>YEAR</th><th>R. McN.</th><th>GOUSHA</th><th>GEN. D.</th><th>YEAR</th></tr></thead><tbody><tr><td>1919</td><td>(A)</td><td>-</td><td>-</td><td>1919</td><td>1946</td><td>46 / 6-</td><td>T</td><td>-</td><td>1946</td><td>1973</td><td>73</td><td>UU</td><td>A21</td><td>1973</td></tr><tr><td>1920</td><td>(B)</td><td>-</td><td>-</td><td>1920</td><td>1947</td><td>47 / 7-</td><td>U</td><td>-</td><td>1947</td><td>1974</td><td>74</td><td>VV</td><td>A22</td><td>1974</td></tr><tr><td>1921</td><td>(C)</td><td>-</td><td>-</td><td>1921</td><td>1948</td><td>48 / 8-</td><td>V</td><td>-</td><td>1948</td><td>1975</td><td>75</td><td>WW</td><td>A23</td><td>1975</td></tr><tr><td>1922</td><td>(D)</td><td>-</td><td>-</td><td>1922</td><td>1949</td><td>49 / 9-</td><td>W</td><td>-</td><td>1949</td><td>1976</td><td>76</td><td>XX</td><td>A24</td><td>1976</td></tr><tr><td>1923</td><td>(E)</td><td>-</td><td>-</td><td>1923</td><td>1950</td><td>50 / 0-</td><td>X</td><td>-</td><td>1950</td><td>1977</td><td>77</td><td>YY</td><td>A25</td><td>1977</td></tr><tr><td>1924</td><td>F</td><td>-</td><td>-</td><td>1924</td><td>1951</td><td>51 / 1-</td><td>Y</td><td>-</td><td>1951</td><td>1978</td><td>78</td><td>ZZ</td><td>A26</td><td>1978</td></tr><tr><td>1925</td><td>G</td><td>-</td><td>-</td><td>1925</td><td>1952</td><td>52 / 2-</td><td>Z</td><td>-</td><td>1952</td><td>1979</td><td>79</td><td>AB</td><td>A27</td><td>1979</td></tr><tr><td>1926</td><td>H</td><td>-</td><td>-</td><td>1926</td><td>1953</td><td>53 / 3-</td><td>AA</td><td>A1</td><td>1953</td><td>1980</td><td>80</td><td>AC</td><td>A28</td><td>1980</td></tr><tr><td>1927</td><td>I</td><td>A</td><td>-</td><td>1927</td><td>1954</td><td>54 / 4-</td><td>BB</td><td>A2</td><td>1954</td><td>1981</td><td>81</td><td>AN</td><td>A29</td><td>1981</td></tr><tr><td>1928</td><td>J</td><td>B</td><td>-</td><td>1928</td><td>1955</td><td>55 / 5-</td><td>CC</td><td>A3</td><td>1955</td><td>1982</td><td>82</td><td>MZ</td><td>A30</td><td>1982</td></tr><tr><td>1929</td><td>K</td><td>C</td><td>-</td><td>1929</td><td>1956</td><td>56 / 6-</td><td>DD</td><td>A4</td><td>1956</td><td>1983</td><td>83</td><td>OB</td><td>A31</td><td>1983</td></tr><tr><td>1930</td><td>L</td><td>D</td><td>-</td><td>1930</td><td>1957</td><td>57 / 7-</td><td>EE</td><td>A5</td><td>1957</td><td>1984</td><td>84</td><td>YL</td><td>A32</td><td>1984</td></tr><tr><td>1931</td><td>M</td><td>E</td><td>-</td><td>1931</td><td>1958</td><td>58 / 8-</td><td>FF</td><td>A6</td><td>1958</td><td>1985</td><td>85</td><td>CP</td><td>A33</td><td>1985</td></tr><tr><td>1932</td><td>N</td><td>F</td><td>-</td><td>1932</td><td>1959</td><td>59 / 9-</td><td>GG</td><td>A7</td><td>1959</td><td>1986</td><td>86</td><td>KX</td><td>A34</td><td>1986</td></tr><tr><td>1933</td><td>O</td><td>G</td><td>-</td><td>1933</td><td>1960</td><td>60 / 0-</td><td>HH</td><td>A8</td><td>1960</td><td>1987</td><td>87</td><td>QD</td><td>A35</td><td>1987</td></tr><tr><td>1934</td><td>P</td><td>H</td><td>-</td><td>1934</td><td>1961</td><td>61 / 1-</td><td>II</td><td>A9</td><td>1961</td><td>1988</td><td>88</td><td>WJ</td><td>A36</td><td>1988</td></tr><tr><td>1935</td><td>Q</td><td>I</td><td>-</td><td>1935</td><td>1962</td><td>62 / 2-</td><td>JJ</td><td>A10</td><td>1962</td><td>1989</td><td>89</td><td>ER</td><td>A37</td><td>1989</td></tr><tr><td>1936</td><td>R</td><td>J</td><td>-</td><td>1936</td><td>1963</td><td>63 / 3-</td><td>KK</td><td>A11</td><td>1963</td><td>1990</td><td>90</td><td>IV</td><td>A38</td><td>1990</td></tr><tr><td>1937</td><td>S</td><td>K</td><td>-</td><td>1937</td><td>1964</td><td>64 / 4-</td><td>LL</td><td>A12</td><td>1964</td><td>1991</td><td>91</td><td>SF</td><td>A39</td><td>1991</td></tr><tr><td>1938</td><td>T</td><td>L</td><td>-</td><td>1938</td><td>1965</td><td>65 / 5-</td><td>MM</td><td>A13</td><td>1965</td><td>1992</td><td>92</td><td>UH</td><td>A40</td><td>1992</td></tr><tr><td>1939</td><td>U</td><td>M</td><td>-</td><td>1939</td><td>1966</td><td>66 / 6-</td><td>NN</td><td>A14</td><td>1966</td><td>1993</td><td>93</td><td>GT</td><td>-</td><td>1993</td></tr><tr><td>1940</td><td>V</td><td>N</td><td>-</td><td>1940</td><td>1967</td><td>67 / 7-</td><td>OO</td><td>A15</td><td>1967</td><td>1994</td><td>94</td><td>NA</td><td>-</td><td>1994</td></tr><tr><td>1941</td><td>W</td><td>O</td><td>-</td><td>1941</td><td>1968</td><td>68 / 8-</td><td>PP</td><td>A16</td><td>1968</td><td>1995</td><td>95</td><td>ZM</td><td>-</td><td>1995</td></tr><tr><td>1942</td><td>X</td><td>P</td><td>-</td><td>1942</td><td>1969</td><td>69 / 9-</td><td>QQ</td><td>A17</td><td>1969</td><td>1996</td><td>96</td><td>BO</td><td>-</td><td>1996</td></tr><tr><td>1943</td><td>Y</td><td>Q</td><td>-</td><td>1943</td><td>1970</td><td>70</td><td>RR</td><td>A18</td><td>1970</td><td>1997</td><td>97</td><td>-</td><td>-</td><td>1997</td></tr><tr><td>1944</td><td>Z</td><td>R</td><td>-</td><td>1944</td><td>1971</td><td>71</td><td>SS</td><td>A19</td><td>1971</td><td>1998</td><td>98</td><td>-</td><td>-</td><td>1998</td></tr><tr><td>1945</td><td>45</td><td>S</td><td>-</td><td>1945</td><td>1972</td><td>72</td><td>TT</td><td>A20</td><td>1972</td><td>1999</td><td>(99)</td><td>-</td><td>-</td><td>1999</td></tr></tbody></table>", "R. McN. = Rand McNally & Co.; GOUSHA = H. M. Gousha Co.; GEN. D. = General Drafting Co.", "Rand McNally map codes are found along the bottom edge of the map area, and use a simple alphabetical coding system, beginning with the letter 'A' for 1919, 'B' for 1920, and so on (see chart above). However, no such codes have actually been found on their road maps prior to 'F' for 1924, and many road maps prior to the early-1930s do not include date codes. These letter codes were generally combined with a numeric code for the map area, and beginning in the mid-1930s two digits indicating the year the map was first drafted, as shown in the example at left below.", "1939 map of Ohio: U.3611", "The '36' shows the year the map was first drafted (1936); '11' means Ohio was the 12th map done that year (they started with '00' for Illinois); and 'U' is the code for 1939.", "1951 map of Ohio: '1-453611V-7'", "Same base code '3611' as before, with '45' added (major revision in 1945?); '1'- prefix for 1951 edition; and '-7' suffix for the 7th revision (the 'V' stands for Velox, a type of photographic paper).", "When the alphabet ran out in 1945, the base code ('3611' in the example above) continued to be used, sometimes with a second 2-digit year added at front, likely indicating a major revision of the map was done, but not a completely new drafting. Then a single digit for the year of publication was added as a prefix, and the revision number as a suffix - see example at right above. With only one digit (prefix) to indicate the year, some ambiguity may develop - does '6'- mean 1946, or 1956? So, other clues may need to be used to determine the correct decade. By 1970, only 2-digit prefixes for the year were used. While Rand McNally has published a few road maps into the 21st Century, they appear to have stopped using map codes, as the latest observed is '98' for 1998.", "**General Drafting** maps mostly have dates on the cover or map title inside, as well as copyright dates starting in the late-1930s, so are relatively easy to date. Starting about 1940, many of their maps have a numeric code inside indicating the month and year of printing, such as '141' for Jan. 1941, or '1049' for Oct. 1949. On maps from 1951 to 1953 these codes take on the format 'YY-M-YY' where the first 'YY' is the year the map was drafted, then 'M-YY' the month and year the map was printed. In 1953 a letter was appended to the code, indicating which printing company was used, with 'P' and 'W' being the most commonly seen. In 1954 the initial 'YY' part of the code was dropped, so that only the month and year of printing were indicated for a few years. At this time they also developed the coding system shown in the chart above, where 'A1' indicates 1953, 'A2' 1954, and so on until 'A40' for 1992, at which time General Drafting was purchased by the Langenscheidt Publishing Group and absorbed into the American Map", "Company. (Occasionally the characters are reversed, such as '4A' rather than 'A4'). These codes do not actually start appearing on maps until 1958 however, and indicate when the map was originally drafted, not when the map was printed - the code for the month/year along with the letter for the printer was still used for that. These two codes at first appeared together with a hypen separator, but by the early-1960s the printing date/company code was moved to the back cover, while the code for the original map drafting year appeared along the bottom edge of each map inside. A progression of examples of codes on Esso maps of New York are shown at right. The convention for dating General", "Drafting maps is that those printed in the Fall are for the following year - for example, the map with the Nov. 1961 code shown in the last example is found on the 1962 edition of the Esso New York map.", "'141' = map printed in Jan. 1941", "'50-5-51' = map first drafted in 1950, printed May 1951", "'556W' = map printed May 1956 by company coded 'W", "'W658-1A' = map printed June 1958, first drafted in 1953 ('1A')", "'W1161' = printed Nov. 1961 'A8' = map first drafted in 1960", "Bottom of back cover", "Corner of map inside", "Gousha also used a simple alphabetical coding system with the codes also found along the bottom map edge, starting with the letter 'A' when the company produced their first road maps in 1927 (see chart above). In 1928 a 3-digit code for the map area was added, along with generally two letters, either 'J.C.' or 'S.C.' though sometimes only a single 'J' or 'S' is used. The meaning of these letters is unknown. See example at left below. In the mid-1930s the codes were divided into two parts, with the letter for the date and the 3-digit code for the area in one part, and a number 1-12 for the month of the year the map was drafted, along with the 'J/C/S' letters in a second part, though often times these two parts are still appended together, while other times they are found in separate areas of the map, though always along the bottom edge.", "1933 map of Ohio: 'G-205-J.C.'", {"bbox": [940, 760, 1118, 803], "category":