I am currently using free-look camera in RCT3.

Though this camera mode doesn't go through terrain or tracks. I want the camera to be able to go anywhere without being blocked by objects.

Also, I know you can turn the terrain visibility on / off. Though, I am looking for the camera to go there and not worry about that visibility.

Is this possible (maybe through options.txt)?

If you get up close enough, it will go through the object above ground...Not sure if that's what you mean!

I'll try and explain it better; also, this question only really applies in free-look camera mode (as the other camera modes are more isometric views).

I have a coaster that drops deep underground, does a corkscrew, and then comes out of the ground.

When I try and go inside the tunnel in free-look camera mode, it does not let me. Instead, the camera instantly warps to the terrain above the tunnel.

The reason I want the camera to go inside the tunnel is so that I can do scenery. So, I just wanted to see if anyone was able to successfully get the free-look camera inside a tunnel. I have a feeling it is not possible.

No, it is not possible to take the camera underground to view what’s down there. The camera will go underwater but it will not go underground.

In addition to re-setting your terrain transparency you will need to excavate a deep temporary hole as close as you can get it to the underground area you want to work with. This is easier to excavate if your park is not already landscaped, if scenery is not already placed on the proposed excavation area or if you can excavate where there is no water. Once you’ve dug your hole you can take the camera down to that level and see closer what you are doing.

Before you do any work though, excavate your hole and immediately try to put the landscape back to where it was before excavating. If you can’t get the land or the scenery that is already on it back to where it should be then go back to the previous save and try again with another spot on your map. In this way you won’t have to choose between the underground changes you’ve made, new terraforming you don’t like or scenery that has convoluted itself into freakish configurations.

After excavating you may also want to temporarily change to a darker cliff face. A dark cliff face is easier to see through than a light coloured cliff face.

As you are probably aware there is a limit as to how high one can drag the landscape up or excavate it down in RCT3. Although terrain building has these limitations there seems to be no limit as to how deep or high the rides can be built or scenery can be placed. If your ride and the scenery you want to place with it will be located below this excavation limit written into the game engine it would help to change the terrain surface inside the excavation to a darker colour, e.g. it would be easier to see through transparent terrain covered with dark rock or grass than covered with beach sand or snow.

If you feel you must see the scenery as it would be viewed from the tunnel I’d recommend taking a ride on the coaster and taking notes and/or making screenshots.