Removed from Venice's palazzo-packed canals and crowds, the 2015-opened JW Marriott is almost a destination in itself. Featuring 40 acres (16 hectares) of manicured gardens, cedars, and magnolias in this former sanitarium, as well as a sharp design that's airy and serene -- think mostly neutral tones with pops of blue. The lobby's powder blues pop against geometric mirrors and polished marbles, while golds add flashy flourishes. Panoramic lagoon and Venetian vistas are sensational from rooftop terraces, where an infinity pool accompanies a bar and restaurant, although a family pool is more child-appropriate. Activities like morning yoga and cooking classes can keep guests busy on-site, though the mostly couples crowd often chooses poolside lounging or spa indulgence. The property has an undeniably romantic vibe, enhanced by its isolated island setting.

Between Venice's lagoon and the Adriatic sea, the hotel's private island, Isola delle Rose, is certainly beautiful, but it's removed from Venice. Free water shuttles run every half hour to Piazza San Marco in 20 minutes, where travelers can quickly immerse themselves in Venice's bridged canal charm. From here, it's a seven-minute walk to the Rialto Bridge, and "vaporetto" water busses/taxis can shorten the otherwise 15-minute walks to the Grand Canal. Venice Marco Polo Airport is a 50-minute "vaporetto" ride, and the hotel has a private dock at San Marco, where its shuttles collect guests. Airport transfers are at a fee.

Spread among five residences, fresh rooms are elegant and minimalist, outfitted in a relaxing palette of neutral tones with pops of blue or green. Entry-level Deluxe Rooms are a spacious 388 square feet (36 square meters), and feature plush chaise lounges, monochrome photography, big desks, and glass doors that lead to outdoor spaces. Entry-level units have garden views, while upgraded rooms have more romantic lagoon vistas. Larger Suites have living rooms, while impressive Villas offer private gardens, plunge pools, and whirlpools.

Standard in-room amenities include phones, large flat-screen TVs, electric kettles, coffee machines, minibars, and electronic safes. Sleek. wood-accented white-tile bathrooms have either showers or deep marble soaking tubs with showerheads. Dual vanity sinks with ample high-end toiletries are provided, as are fluffy robes, slippers, and hairdryers. Rooms can be fitted with cribs. All have individual climate control. Wi-Fi is at a fee, except for Marriott Rewards members, or those on resort packages.

Foodies will find themselves well-catered to here. Though closed Tuesdays and Wednesdays, the Michelin-starred Dopolavoro gets its own 1920s building, where chef Giancarlo Perbellini dishes out gourmet fare. Guests start the day amid Cucina's Scandinavian-esque light woods, where buffet breakfasts consists of made-to-order eggs and a wide array of cooked and continental options (at a fee). The Sagra rooftop restaurant has a chic geometric-print bar, walls lined with Panama hats and wicker totes, and floor-to-ceiling glass that lets in lots of light and afford scenic views. Outdoors is a small adult-only rooftop pool and bar, plus ample loungers and daybeds. The lobby bar serves all-day drinks and snacks, while Dispensa has a menu of coffees, sandwiches, and pastries. Giardina Grill's offers al fresco dining near the Family Pool, both of which are open May through September. 

A movable glass wall at GOCO Spa's indoor/outdoor pool sets a striking tone, but access fees apply for its facilities, which also include a gym, hammam, and sauna. Treatments in its Spa Suites are particularly romantic, plus relaxation zones surround a Himalayan salt wall. Cooking and meditation classes are on offer, as are activities at the kids' club. A resort package is available that includes use of the kids' club and bikes, plus in-room Wi-Fi. Wi-Fi is free in common areas and everywhere for Marriott Rewards members. Shuttles every half-hour to San Marco are free, and run from morning until late. Nine meeting rooms, a ballroom, and church facilities are mostly used for weddings. Designer brands at the hotel's boutique offer on-site shopping, and the concierge is available 24/7.