This is a great find! It looks like a the upper part of a 500 kilo bomb to me. I'm not certain, but the cylindric part could be the upper part where the detonator was fitted. This bomb has obvioulsy exploded. It is probably the relic of an allied bombing of Gilze Rijen . The good condition could be the result of a dry sandy earth with a mix of turf. (the picture shows sandy soft earth) This could have prevented rusting to a certain degree.

__________________