| T Cross Ranch | Stephanie Lowe |
| Table Rocks, Oregon Trail landmark | WyoHistory.org |
| Tarquinio, Enzo | Laura E. Ruberto |
| Tate Geological and Mineralogical Museum | |
| Tax, Mineral Severance | Sarah Gorin |
| Taylor Grazing Act, 1934 | Russel L. Tanner |
| Teapot Dome Scandal, The | Phil Roberts |
| Teapot Dome, Rocky Mountain Oilfield Testing Center and | Carolynne Harris |
| Teapot Dome, U.S. Marines and | Carolynne Harris |
| Ten Sleep | |
| Teno Roncalio Post Office Building | |
| Terry, George, murder of | Dick Blust, Jr. |
| Teton County, Wyoming | Clayton Caden, Shannon Sullivan |
| Teton Forest Reserve | John Clayton |
| Texas Trail Museum | |
| Thaxton, Edith, on Dances in the Bighorn Basin | Washakie Museum and Cultural Center |
| Thayer, John | Wyoming State Archives |
| Thermopolis, Wyo., sale of hot springs by Eastern Shoshone and Northern Arapaho tribes | WyoHistory.org |
| Thermus aquaticus, microbe found in Yellowstone | Rebecca Hein |
| Thomas, Oleta, oral history | Casper College Western History Center |
| Thomas, Ruth, disability activist | Phil Roberts |
| Thomas, Sarah, pioneer grave of | Randy Brown |
| Thomson, Thyra, Wyoming Secretary of State 1963-1987 | Wyoming State Archives |
| Three Crossings, Oregon Trail landmark on the Sweetwater River | WyoHistory.org |
| Thuermer, Angus, Jackson Hole News editor | Kerry Drake |
| Tie Flume, Tongue River | Rebecca Hein |
| Tie Flume, Warm Spring Canyon | Robert G. and Elizabeth L. Rosenberg |
| Tie Hack Memorial | |
| Tongue River Tie Flume | Rebecca Hein |
| Tongue River Tie Flume remnants | |
| Toomey’s Mills | Nicole Lebsack, Stephanie Lowe |
| Toomey’s Mills/the Old Mill Inn | |
| Torrey, Col. Jay L. | Phil Roberts |
| Torrey’s Rough Riders | Phil Roberts |
| Trabing, August and Charles, freighters in Wyoming Territory | Nancy Trabing Mickelson |
| Trade, Native American pre-European contact | Samuel Western |
