About 600 miles off the coast of Ecuador, in the middle of the Pacific Ocean, the Galapagos Islands are a remarkable place to visit for wildlife sightings. You can see flightless Galapagos penguins, Galapagos sea lions, giant Galapagos tortoises, marine iguanas and hundreds of other species found nowhere else on earth.

The islands are also one of the places in the world that are best explored by cruise ships.

To get close to Mother Nature in the mostly unpopulated islands, you need to get on the water — and land on islands in the company of a licensed Ecuadorian naturalist guide. Galapagos National Park tightly controls who comes in and where ships can explore.

All the ships are Ecuadorian flagged, Ecuadorian crewed and owned by Ecuadorian companies, sometimes in partnership with leading cruise companies. Excursions, often twice a day, are included in cruise fares. The sailings are year-round, and routes are always subject to change based on park control.

Related: 9 things I wish I had known before taking a Galapagos cruise

The cruise companies use various descriptors of where they go, but basically: If your ship heads north and west, you’ll see more volcanic landscapes; if you go south or central you’ll explore more beaches and bays. Wildlife sightings on both routes are thrilling, both above and under the sea — where you may find yourself snorkeling with sharks and sea lions.

Birdwatchers may want to do a full 14-night trip to touch every corner and add many species to…