And keep in mind... this is no Laura Croft Tomb Raider styles.
Several items are 'required reading' per race rules, checked off at the beginning and end of the race. These items, without boring you with too many specifics, include (all assumed functional and in working order): cold weather sleeping bag, ax, snow shoes, race promotional material (trail mail, SPOT trackers), cooker & pot, vet book, sufficient fuel (Heet) to boil 3 gallons of water, adequate gang line to secure all of your dogs, non-chafing harnesses for each dog, and emergency dog food.
And then there are the items the twins (and many other mushers) typically carry with them.
For the dogs: jackets, shoulder holsters for hot packs, pills & ointments, snacks, leg wraps, straw, bowls, ladle, cooler, and 'fox tails' (gentlemen, it's cold... use your imagination...).
For the twins: food (jerky, candy, granola, trail mix, Smuckers frozen PB&J sandwiches...), socks, GPS (approved, location providing one-way non-transmitting Garmin), batteries (lots of lithium batteries), bivy, personal care items like disposable toothbrushes, tissue and sun/windscreen sticks, watch with alarm, ski/trek pole for paddling, grabber hand and foot warmers, gloves, heavy duty mittens, face gators, fleece neck bibs that hold small water bottles under their parkas where they won't freeze, under armor, goggles, headlamps, tape (electrical, hockey), super glue, quality fur hood ruffs, and a variety of tools and extra runner plastic. Some mushers have special things to carry, like our friend Charley Bejna, a Type 1 diabetic that requires a fair amount of medical supplies.
When asked at the start of the race what her sled weighed, Anna replied, "um, well, honestly? the better part of 200 - 250 pounds."
A key piece of gear I haven't touched on yet is the sled itself. The race allows for some things and prohibits others. Mushers can use up to 3 sleds during the race, one from the start and 2 shipped out. It must be a sled or toboggan capable of hauling an injured dog(s) to the next checkpoint and the required gear. There are requirements for braking mechanisms, from ice hooks to drag pads. No sails or wheels.
The twins prefer very traditional, standing sleds constructed in great part of wood. Sleds have evolved, however, and are a part of race strategy. Some mushers use 'caboose sleds', aka taildraggers or old man's sleds. They provide the musher a convenient way to sit while traveling, often storing their cooler where it can double as a seat. Even newer designs are being seen on the Iditarod trail this year, sleds with extensive trailer designs that allow a musher to rest 2 or more dogs while continuing down the trail. The advantages of this are still being debated... yes, you rest dogs and rotate them out, but the ones pulling have more weight thanks to their resting friends. These sleds are also sometimes known as 'river sleds', as they more manageable on flat conditions than things like the Dalzell Gorge. Part of the reason the twins have preferred traditional style standing sleds thus far is they find them more maneuverable on technical trail.
We'll see what crosses the finish line in Nome. And what doesn't.