Architecture of Monaco
Although some old ruins do exist in Monaco, such as the city walls and some towers, the city's look didn't develop until much later and today it is essentially a modern city with high rises providing as many water views as is possible.
There are two buildings of architectural note however. The famed Monte Carlo Casino (1858-1863) was modeled after numerous buildings and inspirations, making the structure fairly unique. The second building of note is the Prince's Palace, which was founded 1215 as a Genoan fort, but has adopted every architectural style since that time, giving the building Gothic, Renaissance, and Baroque features among others.