Egypt also hosts an unknown number of refugees and asylum seekers, estimated to be between 500,000 and 3 million. There are some 70,000 Palestinian refugees, and about 150,000 recently arrived Iraqi refugees, but the number of the largest group, the Sudanese, is contested.[nb 1] The once-vibrant and ancient Greek and Jewish communities in Egypt have almost disappeared, with only a small number remaining in the country, but many Egyptian Jews visit on religious or other occasions and tourism. Several important Jewish archaeological and historical sites are found in Cairo, Alexandria and other cities.