Apple just unveiled a brand-new $799 watch called Ultra for extreme athletes that has the company's biggest battery yet

• Apple unveiled a new watch on Wednesday designed for extreme sports, like scuba diving.
• The Apple Watch Ultra is its most durable yet and comes with compass and GPS capabilities.
• It starts at $799 and is available starting on Sept. 23.

Apple rolled out a new Watch on Wednesday that's designed for enthusiasts of extreme activities, like hiking and scuba diving.

The Apple Watch Ultra is built with aerospace titanium and is the most rugged, heavy-duty watch that Apple has developed, the company says.

The watch comes with a bigger and brighter display that makes it easier for the user to read in harsh sunlight. It can be worn with gloves and has better speakers so the wearer can hear even in windy conditions, the company said.

Ultra also has the biggest battery of any Apple watch yet, the company said Wednesday. It comes with 36 hours of battery life on a single charge and 60 hours with a new battery feature that the company is rolling out this fall.

It comes with a compass on the face, improved GPS capabilities, and is customizable for mountain, ocean, and trail activities. The Watch Ultra comes with a night mode that is activated by rotating the crown for better visibility in the dark.

There's a depth feature that monitors the distance and temperature when you're underwater.

Apple is rolling out new bands as well: The Alpine, which comes with a hook that fastens through other loops; an Ocean band that can fit over a wet suit; and the Trail, Apple's thinnest band yet, it said Wednesday.

The company said the Apple Watch Ultra starts at $799. Customers can buy the watch as of Wednesday, and they are available for delivery starting on Sept. 23.

This is the first watch that Apple has unveiled that branches outside of the company's core general fitness audience. It's also one of the priciest. Apple also unveiled its Watch Series 8 on Wednesday, which starts at $399.