The British Museum is to reopen most of its ground-floor galleries on 27 August after being shut for 163 days, its longest peacetime closure. The museum, which first opened its doors in 1759, announced on Friday that it would reopen in time for England’s August bank holiday weekend. It will be one of the last of Britain’s big museums to reopen in a staggered process that began with the National Gallery on 8 July. As at other museums, visitors will need to book a timed slot. Numbers will be reduced and it will feel very different from the usual heaving crowds. Last year there was a 7% increase in visits to 6,239,983, making it the most visited attraction in the UK. Once inside, visitors will follow a single, one-way route that will allow them to see more than 9,000 objects, the museum said, including some of the most popular exhibits such as the Rosetta Stone, the Parthenon Marbles, the Aztec double-headed serpent, the Akan Drum and the Discobolus. Tickets will be available to book from 12 August. Huge demand is likely. The museum’s director, Hartwig Fischer, said: “Visitors are our lifeblood, and we have missed them greatly. It will be wonderful to welcome them back and I do hope that local, London-wide and UK audiences will take this opportunity to discover, or rediscover, the museum, exploring some of the most popular galleries in what will be a much quieter environment.” Initially, only ground-floor galleries will be open, meaning collections that cover ancient Egypt, Greece, Rome and Assyria before moving into Africa, Mexico, North America and the Enlightenment gallery. The artist Grayson Perry has agreed to lend a work that was the centrepiece of his exhibition at the museum nine years ago. Titled Tomb of the Unknown Craftsman, it is an elaborate, fabulously decorated iron coffin ship. Curators hope to display the work in room 17, next to the Nereid Monument from western Turkey, built around 390BC. The museum is reopening cautiously. For the first two days, hours will be 10am-3pm. From Saturday 29 August it will be open 10am-5pm. It plans to reopen some of the upper-floor galleries from 21 September. The museum also announced new dates and extended runs for postponed exhibitions. Tantra: enlightenment to revolution will run from 24 September to 24 January, and Arctic: culture and climate will run from 22 October to 21 February. The display of Edmund de Waal’s library of exile in room 2 has also been extended. The museum said there had been a lot of hard work by staff to get the “splendid yet complex” building back into service. It pointed to objects such as the Lewis chess pieces or Nimrud ivories, which are especially vulnerable to fluctuations in temperature or humidity. “The presence of visitors plays an important part in keeping that humidity stable and we need to be careful as the objects reacclimatise during this first phase of reopening,” the museum said. Fischer added: “The British Museum’s extraordinary collection is a unique place to learn about the shared and complex history of humankind, with its many achievements and challenges, conflicts and innovations. It demonstrates humanity’s ability to endure and create even in precarious times. It will inspire us as we embark on this new chapter in the story of the museum, and the world.”