Decathlon – Portsmouth – Opening Hours & Store Details Decathlon is prominently positioned in Portsmouth Retail Park on Southampton Road, a 1.84 mile driving distance north from the centre of Portsmouth, in Paulsgrove (near to Premier Inn Portsmouth North Harbour). This store essentially provides service to people from the locales of Hilsea, Paulsgrove, Tipner, Port Solent, Cosham, Ports Down, Fort Widley Married Quarters and Horsea Island. If you would like to stop by today (Friday), it is open 9:00 am – 7:00 pm. On this page, you will find operating times, store location, contact number and additional information about Decathlon Portsmouth.