Curve radius is given in meters on these maps. Curve No. 30, at the right-hand bottom corner, causes the lowest speed restriction within this zone (69 mph in mixed operation with freight, 85 mph on dedicated passenger track, if the curve isn't eased). A comparable curve is located directly in front of Red Bluff station, and therefore of no concern.

The underlying map is found on .
© Maps a la carte, Inc, used with permission.
The following link shows the northern approach to Red Bluff station, while this one gives an overview over the speed zone. Navigation, magnification and resizing needs Javascript on that site.