Sorry, kids. Viking River Cruises are for adults only from now on.

The cruise line has updated its travel policy, raising the minimum age of travelers from 12 to 18 as of August 1, Travel Weekly reported. Any customers who have booked before then (regardless of when they depart) but still have family members under 18 will still be able to travel on Viking through the end of 2019.

Otherwise, passengers must be 18 before their date of departure.

“Due to the nature of our cruise and travel itineraries, the carrier does not maintain facilities or services on our ships for individuals under the age of 18 years,” the new policy states.

The new change comes as a way to create uniformity across all of Viking’s lines — the company’s ocean liners already allows only travelers over 18.

“Viking has always offered experiences that are designed for travelers who are 50 and older, with interests in history, art, culture and exploration,” Richard Marnell, Viking's senior vice president of marketing, told Travel Weekly. “We had allowed a degree of flexibility in the minimum age for travel, but increasingly our guests have told us how much they appreciate an environment where they can travel without children.”