Designed by the Dutch architect Rem Koolhaas (OMA agency), the Qatar National Library (QNL) is located in the heart of Education City, the huge Doha campus. Inaugurated on 16 April 2018 – after six years of work – the establishment, which is open to the public free of charge, is accessible via the green line of the metro. From the sky, the QNL resembles two pieces of paper that are pulled apart and folded diagonally at the corners. The 484,376 ft² (45,000 m²) building houses over a million books and can accommodate thousands of visitors. Designed as a single unit, the interior space provides a panoramic view of the shelves and easy access to the books. The Qatar National Library comprises the National Library, the University Library, the Doha Municipal Library and the Qatari Arab-Islamic Heritage Library. Located twenty feet (six metres) underground in the centre of the building, this collection is unique in the Persian Gulf and consists of rare and valuable ancient documents, including archives, books, manuscripts, maps, atlases, photographs, and navigational instruments.