 Some designated properties contain multiple sites that share a common geographical location or cultural heritage.The United Kingdom National Commission for UNESCO advises the British government, which is responsible for maintaining its World Heritage Sites, on policies regarding UNESCO.The UK National Commission for UNESCO conducted research in 2014-15 on the Wider Value of UNESCO to the UK, and found that the UK's World Heritage Sites generated an estimated £85 million from April 2014 to March 2015 through their association with the global network.