| Prospect Hill Interpretive Area | Field Trips | |
| Prospect Hill, Oregon Trail site of | Encyclopedia | WyoHistory.org |
| Public television, Wyoming | Encyclopedia | Doug McInnis |
| Pumpkin Buttes | Field Trips | |
| Race Horse, Bannock off-reservation hunting rights and | Encyclopedia | John Clayton |
| Railroad arrives in Laramie | Encyclopedia | Tom Rea |
| Rawlins-area Mountain Bike Trails | Field Trips | |
| REA, Wyoming history of | Encyclopedia | Kerry Drake |
| Red Buttes BLM Interpretive Site | Field Trips | |
| Red Buttes, Battle of | Encyclopedia | Ellis Hein |
| Red Buttes, Oregon Trail landmark | Encyclopedia | WyoHistory.org |
| Red Cloud’s War | Encyclopedia | Emilene Ostlind |
| Red Fork Battle, 1876 | Encyclopedia | Gerry Robinson |
| Red Gulch Dinosaur Tracksite | Field Trips | |
| Red Onion Museum | Field Trips | |
| Reeb, James, civil rights martyr | Encyclopedia | Phil White |
| Reel, Estelle | Encyclopedia | Kerry Drake |
| Refinery business, Wyoming | Encyclopedia | Tom Mast |
| Register Cliff | Field Trips | |
| Register Cliff | Encyclopedia | WyomingHeritage.org, Wyoming State Historic Preservation Office |
| Reliance Tipple | Field Trips | |
| Reliance, Wyoming | Encyclopedia | Dick Blust, Jr. |
| Reshaw's Bridge | Field Trips | |
| Reshaw's Bridge | Encyclopedia | Jefferson Glass |
| Richards, DeForest | Encyclopedia | Wyoming State Archives |
| Richards, William | Encyclopedia | Wyoming State Archives |
| Richards, William A. and 1874 boundary survey | Encyclopedia | Lucia McCreery |
| Riggle, Herschel Clay “Tricky” | Encyclopedia | Robin Everett |
| Ringo, Martin and J.P. Parker, Oregon Trail graves of | Encyclopedia | WyoHistory.org |
| Riverton Museum | Field Trips | |
| Robert Russin sculptures | Field Trips | |
| Roberts, LeaKae, Cokeville survivor oral history | Oral Histories | Wyoming State Archives |
| Roberts, Rev. John | Encyclopedia | Warren Murphy |
| Rock Avenue | Field Trips | |
| Rock Avenue, Oregon Trail site of | Encyclopedia | WyoHistory.org |
| Rock Church | Field Trips | |
| Rock Springs Historical Museum | Field Trips | |
| Rock Springs Main Street | Field Trips | |
| Rock Springs Massacre | Encyclopedia | Tom Rea |
| Rock Springs Walking Tour | Field Trips | |
| Rock Springs, African American churches of | Encyclopedia | Brie Blasi |
| Rock Springs, Wyoming | Encyclopedia | Chris Propst |
| Rocky Mountain Herbarium | Field Trips | |
| Rocky Mountain Oilfield Testing Center at Teapot Dome Oil Field | Encyclopedia | Carolynne Harris |
| Rocky Ridge | Encyclopedia | WyoHistory.org |
| Rocky Ridge | Field Trips | |
| Rogers, Clifford | Encyclopedia | Wyoming State Archives |
| Roncalio, Teno, biographical essay | Encyclopedia | Joan Barron |
| Roosevelt, Theodore 1903 Horseback Travel Route | Field Trips | |
| Roosevelt, Theodore visits Wyoming in 1903 Visit | Encyclopedia | Rebecca Hein |
