'Harpune' (i) was a series of German simulated preparations for an invasion of the east coast of England by forces based in France, the Low Countries, Denmark and Norway, and as such designed to conceal the departure of substantial forces for 'Barbarossa' (spring 1941).

The operation portrayed 'Seelöwe' as inevitable, and had two parts, namely 'Harpune Süd' (harpoon south) centred on the ports on the southern side of the English Channel, and 'Harpune Nord' (harpoon north) centred on ports in Denmark and Norway.