Wikipedia:WikiProject U.S. Roads/Wyoming/numbering history

A 1963 Gousha map shows four-digit "state secondary" numbers. There is an obvious pattern in comparing old to new numbers. They also match the numbers in the Reference Marker Book.

Albany County

• WYO 10: 0101
• WYO 11: 0102
• WYO 130: 0103
• WYO 12: 0104
• WYO 13: 0105
• WYO 210: 0107
• WYO 34: 0109
• WYO 14: 0103 Spur (now 0110)

Big Horn County

• WYO 30: 0200
• WYO 31: 0201; 0201 Spur (now 0203) is a wye connection at Manderson
• WYO 32: 0202
• WYO 33: 0205 ("new name" only)
• WYO 35: 0206 ("new name" only)
• WYO 36: 0207 ("new name" only)
• WYO 37: 0208

Campbell County

• WYO 50: 0300
• WYO 59: 0301 (now 43)
• US 14/US 16: 0302
• WYO 51: 0303

Carbon County

• WYO 70: 0401
• WYO 71: 0402
• WYO 72: 0404, 0412
• WYO 73: 0406
• WYO 74
• WYO 75
• WYO 76: 0411
• WYO 77
• WYO 78

Converse County

• WYO 90
• WYO 91
• WYO 93: 0502
• WYO 94
• WYO 95: 0504
• US 20/US 26/US 87: 0505
• WYO 96

Crook County

• WYO 116: 0600
• WYO 24: 0601
• WYO 110: 0601 Spur (now 0602)
• WYO 111: 0603
• WYO 112: 0604
• WYO 113
• US 14: 0607

Fremont County

• WYO 131: 0701
• WYO 132: 0703
• WYO 133: 0706
• WYO 134: 0707
• WYO 135: 0708
• WYO 136: 0710
• WYO 137: 0711
• WYO 138
• WYO 139: 0708 Spur (now 0709)

Goshen County

• WYO 151: 0800
• WYO 152: 0801
• WYO 153
• WYO 154: 0803
• WYO 155
• WYO 156: 0805
• WYO 157: 0806
• WYO 92: 0807
• WYO 158: 0807 Spur (now 0802)
• WYO 159: 0808
• WYO 160: 0809
• WYO 161: 0811

Hot Springs County

• WYO 170: 0900
• WYO 171: 0901
• WYO 172: 0902
• WYO 173: 0903
• WYO 174
• WYO 175: 0904
• WYO 176
• WYO 177?

Johnson County

• WYO 190: 1000
• WYO 191: 1001 (now 1000)
• WYO 192: 1002
• WYO 193: 1003
• WYO 194: 1003 Spur (now 1702)
• US 16: 1004
• WYO 195
• WYO 196: 1006
• WYO 197

Laramie County

• WYO 210
• WYO 211: 1100
• WYO 212
• WYO 213: 1102
• WYO 214: 1103
• WYO 215: 1104
• WYO 216: 1105
• WYO 217
• WYO 218
• WYO 219: 1108
• WYO 221
• WYO 222
• US 30: 1111
• WYO 223
• WYO 224
• WYO 225
• WYO 226

Lincoln County

• WYO 231: 1200
• WYO 232: 1201
• WYO 233: 1202
• WYO 234
• WYO 235: 1203
• WYO 236: 1204
• WYO 237: 1205
• WYO 238: 1206
• WYO 239: 1207
• WYO 240: 1208
• WYO 241: 1209
• US 30: 1210 ("new name" only)
• WYO 89: 1211 ("new name" only)

Natrona County

• WYO 250
• WYO 251: 1301
• WYO 252: 1301 Spur (now 1302)
• WYO 253
• WYO 254
• WYO 255
• WYO 256
• WYO 257
• WYO 258
• WYO 259

Niobrara County

• WYO 270: 1400, 1401
• WYO 271
• WYO 272
• WYO 273
• WYO 274

Park County

• WYO 290: 1500
• WYO 291: 1501
• WYO 292
• WYO 293
• WYO 294: 1503
• WYO 295: 1504, 1505 (now also 1506)
• WYO 296: 1507
• WYO 297

Platte County

• WYO 310: 1600
• WYO 311: 1600 (now 1601)
• WYO 312: 1601
• WYO 313: 1602
• WYO 314: 1603
• WYO 315: 1605
• WYO 316: 1604
• WYO 317
• WYO 318
• WYO 319
• WYO 320: 1610
• WYO 321
• WYO 322

Sheridan County

• WYO 331: 1701
• WYO 332: 1702
• WYO 333
• WYO 334
• WYO 335: 1703
• WYO 336: 1704
• WYO 337
• WYO 338: 1706
• WYO 339: 1706 Spur (now 1705)
• WYO 340: 1707
• WYO 341: 1700 ("new name" only)
• WYO 342
• WYO 343: 1709
• WYO 344
• WYO 345: 1712

Sublette County

• WYO 350: 1800
• WYO 351: 1801
• WYO 352: 1802
• WYO 353: 1804
• WYO 354

Sweetwater County

• WYO 530: 1900
• WYO 430: 1903
• WYO 370: 1904
• WYO 371: 1905
• WYO 372: 1906
• WYO 373
• WYO 374: 1910
• WYO 375: 1909
• WYO 376
• WYO 377: 1911
• WYO 28: 1912

Teton County

• WYO 22: 2000
• WYO 390: 2001
• WYO 391

Uinta County

• WYO 150: 2100
• WYO 410: 2101
• WYO 411: 2104 ("new name" only)
• WYO 412: 2103
• WYO 413
• WYO 414: 2105

Washakie County

• WYO 431: 2200
• WYO 432: 2201
• WYO 433: 2202
• WYO 434: 2203
• WYO 435
• WYO 436

Weston County

• WYO 450: 2300
• WYO 451: 2301
• WYO 116: 2302
• WYO 585: 2303
• WYO 452