The Watchmaking Museum contains a collection of clocks, watches and other horological items. The history of the collection presented in the museum dates back to 1814, which makes it the oldest collection of clocks in the world. It has been open to visitors since 1874. Most of the items in the collection come from the years 1600-1850. The most important of them are sea clocks, in particular the famous H5 sea clock, which was created by John Harrison in 1770. He solved the problem of determining longitude.
In the Guildhall Library, visitors will also find the Worshipful Company of Clockmakers. This is one of the main publicly available collections of printed materials and manuscripts about British horology.
Until October 2014, the museum was housed in a gallery in Guildhall, but in October 2015 a new exhibition was officially opened by Princess Anna on the second floor of the Science Museum.