I played at Underground in Joplin once before it closed.
I love Paintball Ridge. It's got something for everyone. There's the big castle, which is really cool to play in. There's the small castle, which I don't really perfer. There's a few speedball fields (I haven't tryed them, I don't enjoy speedball personally) and there's my personall favorite, the two wooden forts in the back.
Now, first things first. You've probably heard things about the staff being rude. I've played there around 10 times, and the staff have always be very friendly. Also, I've seen many reviews saying the field is unsafe, and I disagree. I have never encountered anything at these fields to make it seem unsafe to me.
Now, to get more in depth on each field. The large castle is pretty much the main attraction, and yes, it is really the largest paintball castle in the world. It's shaped like a square and it's about a sixty feet from one side to the other. It's divided into three rooms, the front with main door is about 60 feet one way and 2o the other. Imeaditly after entering that room you have the main ramp to the second floor on your right (I wouldn't recomend going up this ramp, it's almost alway covered). About 25 feet at to your forward right after walking in, you have a tunnel acess door (This is also almost always covered). A little bit forward and to the right you have another tunnel access door with several windows. (Going through there is a bad idea) Also covering the main entrance is a second floor tower in the dead center that always has one or two people in it, so it's pretty much impossible to go through the front. The back right room from the attacking view is innaccessible except from the front rooms access door to the tunnel, (the tunnels are inside the walls) So there really no need to go into that. And the back left has to be accessed from the left tunnels, the front tunnels, or from the second floor access ramp (If your an attacker, this is your best shot into the castle). All of the walls except for the one that divides the two back rooms have tunnes and bridge in them. If your protecting from the second floor, keep an eye out below, you can be shot through the cracks in the floorboards. All things considered, it's great fun, but it's often stacked in the protector favor due to all the little corners and stuff.
The small castle was pretty much a waste. It's really easy to defend from the top, but the problem is, you can't raid it. Everything inside the castle is well within ten feet, making it against the rules to acctully fire inside there.
The wooden forts in the back consist of two simple wooden forts and a space of about 100 yard (maybe a little less...) between them with some small cover. Extremly simple, completly fair and very fun. Paintball Ridge gets a perfect review from me.