Preheat the oven to 180 C / Gas 4. Grease and line a 900g loaf tin.
In a mixing bowl cream together the butter and sugar until fluffy. Add the eggs, one at a time until pale and creamy. Toss the blackberries in a little of the flour then add to the mixture along with the rest of the flour and fold in; do not over-mix. Gradually add in just enough milk to form a smooth dropping consistency. Transfer to the prepared cake tin.
Bake in the preheated oven for for approximately 1 to 1 1/2 hours until risen and golden and a skewer inserted into the centre comes out clean. Remove from the oven and allow to cool on a cooling rack before slicing and enjoying.
You can replace blackberries with any soft fruit. Fresh fruit makes a firmer cake than frozen. If using frozen fruit, you can use it straight from the freezer.