Right, I was half right. A dug out boat shaped coffin was found in a ring ditch in Bowthorpe, Norwich. Loads of good detail on it in the book, but basically its the same shape as some in Yorkshire and with the whole barrow/ring ditch dated to circa 1900 bce.
There is also an interesting assessment of the coffin and its compatriots. Basically saying they are shaped as boats but wouldn't have been usable due to the wood used and the design etc.
Also, one of the barrows at Eaton Heath had a potential boat coffin shaped stain so there may have been one there too.
