I'm in a bit of a pickle... I'm stuck in Seattle for the next two days

while my wife and sister hang out downtown. I want no part of that...
While trying to plot a solo predator hunt for tomorrow, I was trying to think of some public land that I used to go shoot at when I lived here, and all of the places I know of are now subdivisions. So I went on the WDFW site looking for land and came up with two areas in King county. Both are less than 500 acres and they don't really seem big enough to shoot a rifle in. They are stillwater and cherry valley. Does anyone know if these places are good to go for predator hunting? Sorry, I'm new to this whole public land thing, I really don't know where to find legal hunting ground.
If anyone knows about these areas, or knows of a better place, let me know. (include directions)
Thanks
Shane