Macau is a former Portuguese colony, a world-renowned gambling destination, and one of the world's most densely populated spots, with a population of 667,000 people (2016) in an area half the size of Manhattan Island. Returned to Chinese rule in 1999, it is now a semi-autonomous "Special Administrative Region", a status it shares with nearby Hong Kong.
Macau is best known as a major destination for gambling. This goes back to colonial times, when Hong Kong had tight limits on gambling—it was legal only at the horse racing track twice a week—but Macau had casinos. Today, Macau is the only part of China where casinos are legal under the auspices of the "One Country, Two Systems" arrangement. Macau overtook Las Vegas as the world's highest revenue gambling destination around 2008 and now has a substantial lead; several of the major Las Vegas casinos have built new establishments in Macau to cash in on the trend.
Macau is by no means only a gambling destination and other attractions include gorgeous colonial architecture, some of it on the UNESCO World Heritage List, a lovely climate and some fine beaches, and excellent food and drink.