One of the reasons that is often pointed to for Portugal and Spain exploring the Atlantic is that they were searching for a new route to the Spice Islands after the Ottomans monopolized the spice trade with Europe. My understanding is that in response to the Ottoman monopoly, Portugal was able to round the Cape of Good Hope, conquer a number of coastal cities, and monopolize the trade in spices themselves until the arrival of the Dutch in the Indian Ocean. Is this understanding correct, and if so what did the Ottomans do to try to stop it?