The mission was located along the Oregon Trail and a growing number of immigrants brought diseases that the Cayuse had little immunity to. In the fall of 1847 a measles epidemic killed half of the tribe while the white people recovered which convinced the Cayuse that Whitman’s medicine was poisoning them. On November 29 a group of Cayuse attacked the mission and killed the Whitmans and 11 other people and took 50 people captive. This tragedy ended the Protestant missions in Oregon territory and started a war against the Cayuse which ended 1855 when they were all relocated to the Umatilla Indian Reservation.
The site has a visitor center, a paved path through the mission grounds, a paved path to the mass grave, and a paved path to a hilltop monument.
The visitor center is accessible. A .36 mile, paved, flat accessible path loops through the mission grounds which has interpretive signs and outlines of the buildings. The path to the mass grave has a steep section and is accessible with assistance. The path to the hilltop monument may be accessible because it’s paved but it’s also very steep. We skipped it because of the summer heat. There also a section of the Oregon Trail that is lumpy grass and not accessible.
The parking lot has long bus/RV spaces.
Mission 46.04206, -118.46484