Marina di Massa is the larger of the two resorts, centred around the "piazza" and the pier where people promenade and take their choice of ice-creams from a stunning range of home-made ices. 
This is a resort where a car is almost superfluous, partly because it's so easy to get around on a bicycle (these can be hired at reasonable rates), partly because the buses and trains provide a good, cheap service, cheaper than taking one's own car, mostly. 
The beaches at Marina di Massa are divided by breakwaters (breakwaters built with huge lumps of marble, of course !) where the water is shallow and sheltered, good for toddlers.

The features that go towards making this an - almost ! - perfect holiday choice are often not mentioned at all in other brochures or pamphlets.
The breath-taking visual element, the Apuan Alps - the range of mountains 6km back from the beach - rise to some 6,000 ft in less than a 15-minute drive, contributing to the mild climate, but also producing that most famous of all marbles - Carrara marble. They offer, too, superb walks and trekking of all kinds with quite incredibly spectacular views from both above and below.
It is also a real delight to find a corner of the world where the bulk of tourists are the natives themselves. This leads to a further bonus in the form of excellent, reasonably priced, wholly Italian food in the many trattorias and restaurants.

An extremely important feature is proximity to so many beautiful, must-be-visited places, to mention just a few: Florence, Siena, Lucca, Pisa, Volterra, without, however, foregoing the pleasures of a seaside holiday. There are organised excursions to almost everywhere.
The beaches are of fine, volcanic sand, divided between bathing establishments (offering deck-chairs, sun-loungers, parasols, etc.), and stretches of free beach. 
We also have a good hospital in Massa with an efficient Casualty, several large supermarkets open on Sundays during the season, as are most of the shops. 
Various forms of sport are provided for: tennis, roller-skating, riding, mini-golf, swimming-pools, etc..