This is Londinium career scenario, with 105 luxury palaces. This city does not and cannot qualify as a "Century of Palaces" city as it cannot remain stable more than a couple of years (in practice, it will be even less than that). This is because the maximum possible wine imports in this mission are 34, which will only support around 70 palaces long-term. Most of the palaces have been held at large villa until near the end for this reason. Some wine has been stockpiled, but the ships won't sell any more when there is more than 40 in the city.
It would in fact be possible to raise yearly wine imports to an absolute maximum of 40, using twin docks on the smaller of the farming islands and serious micromanagement, but this would probably lead to troubles with oil, and would only support a little over 80 palaces anyway. Such a city would still not survive a free run of any more than a couple of years.
This was played ion Very Hard difficulty. The only real difference is that tax income is lower and invasions are bigger. I have used lions on the two largest invasions, the locations of these can be seen.
There are two saves, the first does not attempt to win the mission, the save including "Win" has the necessary culture buildings to achieve victory at the end of the current month.