Clues and packing tips abound, but the destination remains a mystery until the last minute.

To surprise her husband-and herself-33 year old Britni Vigil signed on for a 3 day trip with Pack Up and Go, a tour operator trafficking exclusively in surprise trips, as in travelers haven’t a clue where they are going until they reach the airport. The notion of trips hinging upon suspense is gaining momentum with millennials, honeymooners, high level executives, and the average need-to-escape-the-grind worker bee, all signing on to cede control of their vacation plans. Whether spending $850 on a long weekend domestically or tens of thousands on an exotic multi-week jaunt, travelers are looking to ditch predictability (and foraging through Google’s slog of vacation options) and tap into something often lacking in today’s travel landscape: mystery.

PACK UP AND GO burst onto the scene three years ago offering budget friendly 3 day getaways in the United States by plane, train or car. The price tag includes air fare, lodging (usually design -focused boutique hotels that showcase the city’s character), but the daily itinerary is determined by travelers themselves. How it works: An initial survey establishes budget, gages interests and determines the style of trip (action, culture, relaxation). A week before departure, travelers receive an email with a weather forecast and packing list (bathing suit, hike boots).  A physical envelope (to be opened at the airport) arrives a day or two before departure containing flight and hotel information. Trips involving plane flights average about $850; Road trips are $400

Similarly, The Vacation Hunt offers reasonably priced, flat fee trips (ranging from 3-14 days and staying at budget-conscious lodging in the city centers) but with the added thrill of emailed clues (“Hope you enjoy indulging! Your surprise destination had over 1,000 beers to try!”, referring to Brussels) seededthroughout the period between booking and departure. Along with a survey, owners Roshni Agarwal and Jeff Allen stalk social media to assess clients’ interests and appropriately pair them with a destination. Packages like “All-American Adventures” (starting at $750 per person for 4 days ) and “International Intrigue” (starting at $950 per person for 4 days) include flights, accommodations and at least two activities such as a food tour or entry to a museum. Special occasion travel like an anniverary, baby moon or and honeymoon ( popular with millenials) is the company’s sweet spot, 5-6 day international trips to spots like Portugal, Spain, Aruba or Panama starting at $1250 per person.

Millenial-skewing Anywhr focuses on on lesser-known spots within Asia, Europe and Oceania, say Yilan, a hot spring peppered town in northeast Taiwan with whale watching, and night markets or  Darwin, Australia’s tropical northernmost tip known for coves of crocodiles, aboriginal culture and hiking through Kakadu National Park. Transactions are executed entirely on line (there is a live chat option) using a mix and match system to create a client profile according to type of vacation (adventure, relaxation or wildcard which means open to anything), interests and accommodation preference which can range from hostel and home stays to hotels. After signing on, you’ll receive a teaser email to help with packing. Then, a week before departure, a physical “travelogue” arrives with flight and lodging details, local recommendations and $30 worth of the country’s currency.Trips start at  $330 is for 3 day within the same region (eg. from Europe to Europe) and can go up to $10,000 for a 15 day honeymoon with luxury hotels.
On the high end, Black Tomato’s Get Lost Program can involve up to 6 months of planning and features luxury elements like helicopter transfers and stays at swanky pop-up tents in remote corners of the globe. Those booking this style trip pay a premium to disconnect from everything in a magnificent setting complete with frill-filled, daily activities that deliver adventure without risk (support staff waits in the wings). Travelers customize the level of “escapism” they want and then choose filters such as the environment (polar, jungle, desert, mountain or coastal) and maximum flight time. Some “roll the dice” and know nothing until they reach their destination, (think Mongolia, Svalbard and Guyana) an even pricier option which involves flying privately (with windows blacked out) and a survival “kit” upon arrival containing a satellite phone with an off the grid mapping system, pre-programmed check points as well as technical clothes based on the environment. A recent 3 day group trek in Morocco was priced at  $5800 per person.  A 7 day  private trip to a remote location starts at $20,000 per person and includes 24 hour support monitoring progress, on the ground physical support and all supplies (rafts, stoves canoes)  necessary at designated checkpoints. Flights are not included in trips.

This post originally appeared in The New York Times