Marston Sewage Treatment Works, Lincolnshire. 

Map Key

Blue - BH - Bird Hide from c/pk walk along main track then first left under trees
to the hide or stay on track to works road.
Orange - P - Paddock from c/pk walk along Barkston Road 
then first right down Hougham Mill Lane to main track.
Green - SW - Sewage Works from star walk along road under railway bridge 
to River Witham then follow river to Barkston.
1 - Ouzel Field
2 - Whooper Field
3 - New Workings
4 - Willows
5 - Horse Paddock

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