Maryhill Loops Rd is a public road that is typically closed but can be rented out for weekend events and such. I went on one such tour this weekend. Due to weak (/absent) 3G coverage in the area, I have no Tesla telemetry data. My GPS data from my dash camera is usable, just not as rich/frequent as the Tesla telemetry. As a result the visualization isn't as good. But here it is nonetheless: According to the dashcam GPS data, my top speed for the day was 73mph (though the MP4 only caught 72): Of course, this isn't including highway travel.