According to the Old Testament, David, king of the two partial kingdoms of Judah and Israel, won Jerusalem from the Jebusites around 1000 BC. He moved his seat of government to Jerusalem, making it the capital and religious center of his kingdom. The Bible says David's son Solomon built the first temple for Yahweh, the God of Israel. Jerusalem became the center of Judaism.

The Neo-Babylonian King Nebuchadnezzar II (3rd from the left) conquered Jerusalem in 597 and again in 586 BC, as the Bible says. He took King Jehoiakim (5th from the right) and the Jewish upper class into captivity, sent them to Babylon and destroyed the temple. After Persian king Cyrus the Great seized Babylon, he allowed the exiled Jews to return home to Jerusalem and to rebuild their temple.

The Roman Empire ruled Jerusalem from the year 63 AD. Resistance movements rapidly formed among the population, so that in 66 AD, the First Jewish–Roman War broke out. The war ended 4 years later, with a Roman victory and another destruction of the temple in Jerusalem. The Romans and Byzantines ruled Palestine for approximately 600 years.

Over the course of the Islamic conquest of Greater Syria, Muslim armies also reached Palestine. By order of the Caliph Umar (in the picture), Jerusalem was besieged and captured in the year 637 AD. In the following era of Muslim rule, various, mutually hostile and religiously divided rulers presided over the city. Jerusalem was often besieged and changed hands several times.

From 1070 AD onward, the Muslim Seljuk rulers increasingly threatened the Christian world. Pope Urban II called for the First Crusade, which took Jerusalem in 1099 AD. Over a period of 200 years a total of nine crusades set out to conquer the city as it changed hands between Muslim and Christian rule. In 1244 AD the crusaders finally lost control of the city and it once again became Muslim.

After the conquest of Egypt and Arabia by the Ottomans, Jerusalem became the seat of an Ottoman administrative district in 1535 AD. In its first decades of Ottoman rule, the city saw a clear revival. With a British victory over Ottoman troops in 1917 AD, Palestine fell under British rule. Jerusalem went to the British without a fight.

After World War II, the British gave up their Palestinian Mandate. The UN voted for a division of the country in order to create a home for the survivors of the Holocaust. Some Arab states then went to war against Israel and conquered part of Jerusalem. Until 1967, the city was divided into an Israeli west and a Jordanian east.

In 1967, Israel waged the Six-Day War against Egypt, Jordan and Syria. Israel took control of the Sinai, the Gaza Strip, the West Bank, the Golan Heights and East Jerusalem. Israeli paratroopers gained access to the Old City and stood at the Wailing Wall for the first time since 1949. East Jerusalem is not officially annexed, but rather integrated into the administration.

Israel has not denied Muslims access to its holy places. The Temple Mount is under an autonomous Muslim administration; Muslims can enter, visit the Dome of the Rock and the adjacent Al-Aqsa mosque and pray there.

Jerusalem remains to this day an obstacle to peace between Israel and Palestine. In 1980, Israel declared the whole city its "eternal and indivisible capital." After Jordan gave up its claim to the West Bank and East Jerusalem in 1988, the state of Palestine was proclaimed. Palestine also declares, in theory, Jerusalem as its capital.

The center of Vienna could end up on the UNESCO danger list, amid concerns about high-rise buildings. A large tower could be built on the edge of the area, which includes St. Stephen's Cathedral, Vienna's ornate town hall, and the Hofgarten Imperial Palace (pictured).

The Kathmandu Valley could also be set to enter UNESCO's endangered designation. The valley area includes seven monument zones, three of which were badly damaged in the 2015 earthquake that killed more than 7,000 people. Buddhism and Hinduism fluorished in tandem in the valley over centuries, producing a powerful artistic fusion. Joining the list could mean extra funding for rebuilding efforts.

Israel has protested against the inclusion of Hebron's Old Town as a contender, saying it is insensitive to Jewish culture. The Tomb of the Patriarchs is said to be the resting place of Biblical figures such as Jacob, Isaac and Abraham - making it important in Christianity, Judaism and Islam. However, the Palestinian Authority was warned that it focused too much on Islamic culture.

From 1890 to 1941, Eritrea was an Italian colony. The regime of Mussolini was keen to establish an Italian stamp on the city of Asmara, which is Eritrea's capital today. A whole range of modernist buildings are included in the UNESCO application, including cinemas, banks, gas stations and this shopping center and apartment complex.

The Talayotic culture existed during the Iron Age, on the Balearic island of Menorca. The name is derived from the talaiots, abundant and emblematic structures that can be found on the island. It's thought the Talaiotic people were of Sardinian origin. A striking structure is the Naveta d'Es Tudons, a tomb that is one of the main tourist attractions of Menorca.

Yazd is the capital of Iran's Yazd province and has a unique form of Persian architecture. It's thought to be the world's oldest adobe city and it would be the first still-inhabited city in Iran to gain UNESCO-protected status. The city lies on a flat plain surrounded by mountains and was an important center for Zoroastrianism. Many there still belong to that faith.