Culture Harbours & The Solent Tier 1 Tier 3 Vintage & Historical Portsmouth Uncovering the Secrets of Burrow (Rat) Island in Portsmouth Harbour – Exercise Magwitch by Paul Gonella 3 May SHARE Facebook Twitter Pinterest Burrow Island (often referred to as 'Rat Island') sits in Portsmouth Harbour but is off limits to the public as it is MOD property. Last..