Need a suggestion for a Marriot hotel on the beach

It's kind of close to Miami, but I've stayed at the Harbour Beach Marriott in Ft Lauderdale several times for work and it's lovely. Great pool area, nice beach for walking, good restaurants close by. They had just added the spa last time I was there so I don't have any feedback on that, but I know that they have one.

We were at the Harbour Beach Marriott last Labor Day weekend. While it fits your requirements, just be aware of the fact that it will probably be noisy and crowded with lots of kids if you are there over the holiday weekend. We had a hard time finding chairs at the pool. Also found it annoying that they held a number of kids' events (such as limbo contests with blaring music and lots of yelling) right at the pool. We stayed on for an extra couple of days after the long weekend and found it much more enjoyable and relaxing.
Agree with snowrooster that the pool, beach, restaurants are very nice. I did not use the spa facilities but they looked very nice as well. I believe thay have a separate pool in the spa area so that might one way to avoid the main pool during busy times.

marriott just spent a fortune creating a spa at their Marco Island resort. Lovely beach. You could also forgo the beach and do the JW Marriott in Orlando and do the Ritz Spa which is on the same property.

http://marcoislandmarriottspa.com/

http://www.grandelakes.com/
photogallery.cfm#spa

LMF

I haven't stayed in the other Marriotts suggested but I love the Sawgrass Marriott outside Jacksonville. I isn't on the beach but they have a beach shuttle that runs all the time and great pools.

Marriott on Kaanapali Beach in Maui.

Oops, sorry, I didn't read the Florida part. Disregard my post.

Also another choice is the JW Marriott Grande Lakes in Orlando. Its adjacent to the Ritz Carlton (also part of Marriott hotel family)which has a beautiful Spa. Their pool area is gorgeous and it also has a "lazy" river where you float in supplied inner tubes down the river. Great restaurants on property.

I have been to the Marco Island one and enjoyed that, too, but the JW Marriott is more upscale. I have not had the pleasure yet of visiting their spa, although I know its brand new.

Also, the Ritz Carlton Golf Resort in Naples have been rated as one of the top hotels in the US in the Travel & Leisure magazine with a beautiful spa. It has a complimentary shuttle to its sister property that's right on the beach - you could then have the best of both worlds. They say the Golf Resort is a bit more laid back whereas the Beach one is more dressy (go figure).

Spa at the Harbor Beach Marriott in FLL is nice. Had a massage there that was great. Another perk is that they let you use the spa facilities for the whole day, including a private pool!

Another vote for Marriott Harbor Beach Resort in Ft.Lauderdale. Lovely resort.

Marriot Resort and Spa in Marco Island. Just had a multi million dollar renovation.With a new Spa. It is also on the beach.