Works to the Tigne tunnel are now complete pending Government certification. The tunnel was built by Midi plc as one of the obligations in its contract with Government. Considerable delays to the tunnel were the result of the major engineering work required to preserve the overlying Garden Battery, a 19th century fortification system that was not originally scheduled to be conserved according to the Outline Development Permit. The tunnel was designed to cater for two-way traffic in an urban, built-up area and was built to the size and specifications stipulated by the Outline Development Permit (ODP) and  the scheme approved by the Malta Environment and Planning Authority and by the Roads Department.