Europeans began to explore new trade routes to connect them to Indian Ocean trade in the early to mid 1400s because of the threat posed by the Ottoman Empire to the existing Silk Road. The Ottomans were able to control key chokepoints along the Silk Road, allowing them to levy heavy tolls on merchants passing through these areas. This hindered the flow of goods between Europe and Asia, and led European powers to search for alternative routes to access Asian markets. The exploration of the Atlantic and Pacific oceans was an important part of this process, as Europeans sought to establish direct trade connections with India, China and other Asian markets.