Just north of the tip of Provincetown is a sand-and- gravel rise in the ocean named Stellwagen Bank. Nineteen miles long and six miles wide, the bank causes an upwelling of nutrient-rich currents on either side that supports an aquarium of ocean life. Among the sealife present are dolphins, sea turtles, and, of course, whales. There’s nothing quite like being in the middle of the ocean and seeing the giant fluke of a leviathan crest above the blue waves—or if you are lucky, seeing a humpback or right whale breach before your eyes.

The two fleets that leave from Macmillan Wharf both guarantee sightings of these magnificent creatures. Portuguese Princess Excursions (800/826-9300, www.provincetownwhalewatch.com, Apr.–Oct.) bills itself as an ecofriendly whale watch, with naturalists who collect data and provide an environmental commentary. The Dolphin Fleet (Macmillan Wharf, 800/826-9300, www.whalewatch.com, Apr.–Oct.) is the older and more experienced outfit, touting itself as being especially child-friendly. The two companies recently merged in 2009, ensuring consistency in prices, which are $39 for adults and $31 for children 5–12. Both have regular trips in the morning, afternoon, and at sunset.