gas warfare traing trenches Porton Down

[Bert Heyvaert]

I read in a book called managing historic sites and building, published by English Heritage, that the trenches where tests for gas warfare were done, are preserved on Porton Down, Wiltshire. The whole network should be more than 400m long and is a scheduled ancient monument.

I wondered if anyone knows if these are accessible for visitors.

regards,

Bert