"Survivor" has remained a hit show in part because it's so well-produced. Most of what makes it a successful show isn't obvious on screen, but the impressive work of literally hundreds of crew members makes everything we see on screen possible. Here are seven things you may not have known before about how the show comes together behind the scenes, from legal documents to aerial footage.

Producers pick, and even buy, the cast's clothes

How did each of the two tribes on "Survivor San Juan Del Sur" end up wearing clothing that just happened to match their tribe's color? It wasn't coincidence, but design. The Survivor rule book notes that clothing brought on location must be pre-approved, but that isn't the full story. The show's producers select clothes that not only help viewers identify them visually, but clothes can also help illustrate the role that the cast member has been cast to fill. Producers sometimes even buy bathing suits and clothes for contestants, asking them to wear something they might not normally wear. Eventual winner John Cochran didn't even wear sweater vests before the show, but it helped define him as smart and nerdy.

Aerial footage of challenges is not of the Survivors

During a challenge, we often see the action as filmed from a helicopter. Yet when the contestants are filmed by cameras on the ground, no helicopter is visible or heard. That's because the challenge is recreated days later using stand-ins from the Dream Team, the crew members who help build and test challenges. They wear similar clothes so they match the contestants; there's even a Jeff Probst stand-in. This was first revealed during "Survivor: The Australian Outback," but it's such a convincing effect that it's easy to forget, even when you know that it happens every challenge. Of course, it doesn't change the results of the challenge at all, it just contributes to the way "Survivor" looks.

The cast rides, not walks, between camp and challenges

While contestants leave their tribe camps and enter challenges and Tribal Council by foot, they're transported between locations: generally in vans with blacked-out windows, but sometimes by boat, depending upon the location. That's because places may be located several miles apart. A no-longer-updated web site called Survivor Maps used to illustrate the locations of the major production areas, showing just exactly how much territory the production covers.

The cast walks through every challenge

Jeff Probst's succinct description of a challenge and its rules is just the start of what actually happens. Each tribe walks through the challenge separately, asking questions of Probst and challenge producer John Kirhoffer. They're accompanied by someone from CBS' standards and practices, who makes sure that the challenge is fair, and any critical information told to the tribe is repeated for the other tribe. The cast only runs the challenge after it's been extensively tested, making sure it's doable and looks good on camera.

There are places off-limits to the tribes

Each tribe's camp or beach may allow the players to wander and strategize, but there are limits to how far the cast can go. That's because they might run into another tribe's camp (in Brazil, for "Survivor Tocantins", the tribe camps were located just down a river from one another) or into the camera camp, an outpost for the crew. That's where crew members store cameras and batteries, rest on cots, and eat meals.

Family members also sign releases

As part of the Survivor cast contract, immediate family members are asked to sign a contract that restricts what they can do and say related to "Survivor." They're also asked to sign an "appearance and liability release." (You can read those Survivor legal documents here.)

It takes hundreds to crown one "Survivor"

On screen, "Survivor" appears to be 18 contestants and host Jeff Probst. But off screen, there are hundreds of people working to make it a success, most of whom the contestants will never see or meet. Many of those crew members are from around the world and work with "Survivor" every season, but the show also hires local laborers and others, too. That includes a massive catering operation that feeds all the crew members, transportation crews, and construction crews that build challenges and the Tribal Council set, never mind camera crews, producers, and support staff. Their names flash by in a second at the end of every episode, but they're really the people who make "Survivor" possible every week.