Northways Bench
  This was originally developed as a way of making a curved, heavy bench. It is made in two halves, each similar in construction, using pegged mortice and tenon joints.  
[picture - detail of joint]
  They are joined by oak fishplates secured with square oak pegs hammered into round holes.  

  This design allows for a deeper bench of around 400mm or more, and can be supplied straight or in various radius curves.

Simple, robust

[link to pdf download]