The former is what I had in mind. I ask because it's one of the first constructions my former employer (a landscape architect) asked me to build... But he had no idea of how to go about it and had no desire to give me the time to work out joinery... 12" galvanised lag bolts.

It was altered from the pure form by incorporating it into a fence and adding a solid gate. It was the outside entrance to a japanese influenced garden.

Pretty much everything we did used ERC for the priciple posts, all with the bark still. He and his neighbor lived in a large stand of it.