By or Ing?

[irland5]

Hello,

My question is about whether I have to use by or not:

My house is 30 minutes from here driving or by driving?

My house is an hour from here walking or by walking?

What about if you want to use another means of transport like a bicycle? 30 minutes by biciycle? Is that ok?

Regards

 

[MikeNewYork]

Did you mean that the indefinite article is optional in the first sentence?