How to make mountains?

Hello,
i made flat ground, now i want to create mountains like in minecraft, how can i do it? what is the best way?
Thanks all for help!

 

first get a molehill...

going to need to know a bit more about what you are trying to make, it's an open ended question really. Unless you are literally making a minecraft clone?

 

Ok, I`m trying to make a map like minecraft one with mountains water and more, i dont know how to make the mountains from blocks, i dont have idea about how to make them. The map must be half mountains half flat we may say...
How can i do it? what things i have to use?
Thanks for help bro!

 

The term you might be looking for is "Voxels". In any case, here is a tutorial I once found on the subject; it seems promising: http://forum.unity3d.com/threads/tutorial-procedural-meshes-and-voxel-terrain-c.198651/.

The turtorial (series) has quite some pictures and code snippits. Take a look at the pictures to determine whether this is what you are looking for. If it is you could try to follow along.