Attempt to visit Tohono O'odham Nation Cultural Centre and Museum

Yesterday our goal was the Tohono O'odham Nation Cultural Centre and Museum at Fresnal Canyon Road, Topawa, 10 miles south of Sells. We didn't find it! We found the Post Office (open but nobody there but a sleepy dog) and the school but not the Cultural Centre. We were very disappointed as the woman at the Amerind Museum had told us that it was really worth a visit. There were no signs that we could see so, hopefully, someone might pass that on to them. However, it was not a wasted day because the journey there (more than 2 hours) is very scenic.