I'd echo the points made above - particularly as I believe there are 85+ AC hotels now added to the Marriott brand.
As Pingreeman points out, they have been categorized across a wide range of Marriott brands. The great majority are deemed Courtyard-equivalent, though 4 are now "Autographs".
The great majority (75+) are in Spain, with 11 in Italy and the remainder in Portugal.
The distinguishing feature of the AC's is claimed to be their "urban location" - though it pays to be a little careful because this doesn't always mean "city centre" - and modern character/ambience.
You might also want to note that Marriott have also recently added part of the Italian Boscolo chain to its portfolio. These see themselves are "luxury" establishments.
arkwright - because I am a numbers person, I was wondering where you came up with 85+ AC properties. According to the AC website (Top Luxury Hotels | Luxury Boutique Hotels | Historic Hotels) there are only 27 listed. Ditto on the Marriott site where you filter by brand.
Pingreeman, Yes I too thought that discrepancy looked strange. As is often the case, I think the explanation lies in the differentmethods of classifications used across the various"hotel" sites.
The link you sent to me routes to the Autograph collection - which does indeed list around 27, pitched at relatively high (and few) brand levels. Go to the general Marriott site, by contrast, search for Spain in the "Find a Hotel" window and you'll find 84 hotels lists under six brands. The great majority of these are AC Hotels (70+), classified at the equivalent to the conventional Marriott CY establishment; The same type of distribution - though off a much smaller base level - is shown on the Italy page.
To complicate matters, I have the feeling that there is some overlap between the two sites we are referring to.
I'm not sure that I've answered the question very clearly, but I hope the general drift comes across.
Have a good w/e,
Aha! I see what you mean. I believe the discrepancy lies within how Marriott categorized the ACs under two buckets: "AC" and "Autograph Collection" yielding two sets of hotel brands albeit one-and-the-same. My search by brand was "AC" only as to why I had but 27 world-wide. Using your approach and combining both bucket classes, I see 75 total for Spain.