Voxel based 3d game (Some Knowledge)?

I'm trying to make a voxel based block game (minecraft/terraria) i have some experience in java, c#, lua, c++ and html. And I'd like to make a 3d block based voxel game. My problem is that I don't know were to start in the 3d department and voxel part. I don't want to use unity 3d.

The game is going to be an rts so if any help with that would be helpful. All i need are some pointers or other helpful things.

Thank you.

Added (1). Sorry for my bad English.

Joshua 21.05.2015

I'd go the OpenGL route. You can use LWJGL to do this with Java.
Drawing cubes is relatively simple, just find a good LWJGL tutorial to learn the basics.

Here's one about creating a voxel engine

Chris 21.05.2015