Went on a weekend break to visit Oxford . Stayed at the Bridge Hotel at Shillingford . We went for a walk down the Thames for about 3/4 of a mile and came across this building nestling in the trees about 100 yds from the River . Went exploring and it looks like WW2 building but with a massive entrance .Turns out to be a defensive position for I believe a Howitzer to Guard the river . This is my first post and I struggled a little with camera settings .But I was impressed at the condition of the building after all these years .I guess the tree's hide it from view in the summer months and it looks like it is surrounded with a stream . Not the case on close inspection .