I like the boarded bench and it is on my list of things to build. I was thinking white oak as I expect it to be exposed to weather. I've never worked with white oak before.
Chris Schwarz has an older article about a similar bench called White Water Meeting Bench. I looked for it now from popular woodworking and the pictures don't work but maybe you can find it. I do have pictures I took from a library book. It looks similar but the rails are narrower and there is no bottom shelf.
I think I will go with a mix between the two, with wide rails but no bottom shelf. I like the idea of cutting a notch for the rails to set into but that's a decision to think about later.
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