Casio Pro Trek PRJ-01: The first fully analog outdoor watch

Casio's Pro Trek PRJ-01 Is the First Fully Analog Outdoor Watch the Line Has Ever Produced — and That's Exactly the Point

There is a particular kind of frustration that builds when you strap on a hiking watch and spend the first ten minutes of a trail figuring out which button unlocks the barometer. Casio's Pro Trek lineup has always occupied an interesting middle ground in the outdoor watch space — respected for its toughness and sensor suite, but perpetually guilty of front-loading complexity onto guys who just want to know what time it is and whether their watch will survive a river crossing. The brand appears to have finally listened. The new PRJ-01 is, by every meaningful measure, the most stripped-down Pro Trek ever built, and for a certain kind of buyer, it might also be the best one.

A Brand Known for Feature Overload Pivots to Restraint

Casio's Pro Trek lineup has long been a favorite of outdoorsmen and mountaineers for both its toughness and its digital suite, delivering features like the Triple Sensor — comprising a compass, barometer/altimeter, and thermometer — alongside Tough Solar charging, all at an accessible price point. For a certain buyer, that's a remarkable package. A hiker heading above tree line wants to know if the pressure is dropping before a storm rolls in. A backcountry skier benefits from an altimeter when visibility collapses. These are tools with real utility, and Pro Trek has delivered them reliably for decades.

But the outdoor enthusiast population is far broader than the mountaineer demographic. Most rugged watches now pile on GPS, phone notifications, a stack of sensors, and yet another screen to charge — and that is exactly the part a lot of buyers never actually wanted. The weekend hiker doing day trails in the Smokies. The fly fisherman standing in a cold river at dawn. The guy who camps twice a year and runs on weekends. These users want durability and legibility, not a wrist-mounted instrument panel that requires a manual to operate.

Over the past couple of years, the Japanese watchmaker has been working toward simplifying the Pro Trek lineup, as seen with the PRJ-B001 in 2024 — a watch that notably pared back the formula by ditching the Triple Sensor, cleaning up the dial, and giving buyers a mostly analog display. The PRJ-B001 was a clear signal of intent. The PRJ-01, announced this July, takes that signal and drives it to its logical conclusion.

The PRJ-01: What Casio Actually Built

A Fully Analog Dial, First in Pro Trek History

The PRJ-01 is a big departure for Pro Trek, a line that has been defined for decades by digital readouts, triple sensors, and connected features. The new series ditches all of that in favor of a clean analog dial with wide hour and minute hands and a thin seconds hand. This isn't a hybrid display with a sub-dial readout hiding GPS data underneath the analog face. There is no digital layer at all. The PRJ-01 is the only current Pro Trek with a full analog display. That alone makes it a landmark product in the brand's history.

The dial features a simple three-hand layout for easy time reading, along with a date display. High-contrast colors emphasize the hands and indexes, improving visibility in outdoor settings. Simplicity here is a feature, not a concession. When a trail runner checks his wrist mid-stride or a paddler glances down through a spray shield, a clean three-hand analog face with bold contrast beats a cluttered digital display every time. Despite omitting the Triple Sensor, Casio still brings a few useful features, including the date window positioned at 4:30 and a low-battery alert. That low-battery alert is delivered practically: the second hand jumps two seconds instead of one when the battery runs low, a mechanical signal that requires no screen, no buzzer, and no companion app to decode.

Solar Power, But Not Tough Solar

The PRJ-01 runs on solar charging, which means it draws power from both sunlight and ambient indoor lighting to keep the movement running indefinitely under normal use. Casio claims the watch can operate for approximately five months on a full charge, even without further exposure to light. That is a strong reserve for an analog watch being worn daily through varied seasons. However, there is an important distinction worth noting for buyers who know Casio's lineup well. This solar-powered watch does not have Tough Solar, which means it does not have the power-saving function that conserves power in dark environments — a feature found on higher Pro Trek models.

Tough Solar, as it appears on models like the PRW-3500 and PRW-6900, actively enters a power-save state when the watch remains in darkness for extended periods, drastically extending reserve time. The PRJ-01's system doesn't do that. But given that any watch worn on a wrist sees daylight regularly, and that five months of reserve is already exceptionally generous for the average user's charging habits, this is a limitation that will almost never matter in practice. The dial is fully phosphorescent, meaning the entire white background glows in low-light environments to provide contrast against the hands and markers, and is also light-transmissive, which allows the built-in solar charging system to draw power from sunlight and indoor lighting. That dual-purpose dial design is genuinely clever — the same material that charges the watch also serves as its after-dark readable surface.

A Phosphorescent Dial Replaces the Backlight

Here is where some buyers will need to make a considered decision. The watch employs a white, full-screen phosphorescent dial that enhances readability in the dark, including during night hiking. The entire dial glows in low-light conditions after absorbing light from a headlamp or other sources, a feature made possible by the light-transmissive solar dial. On a technical level, that's impressive. Rather than coating only the hands and hour markers — which is the standard approach on most analog watches — Casio has made the entire dial face glow, creating a high-contrast background that remains legible when the hands pass over it.

The trade-off is real, though. There is no button-activated backlight like past Pro Treks, leaving users subject to the lume's charge for nighttime visibility. A dead-of-night tent check when you haven't been near any light source in hours will be more difficult with the PRJ-01 than with any digital Pro Trek. Anyone who needs nighttime button illumination should know the luminous dial helps but needs a light charge first and fades, so digital Pro Treks with dedicated backlights suit anyone regularly checking the time in the dark. That caveat is honest and worth taking seriously — but for day hikes, campsite evenings, and general outdoor wear, the phosphorescent dial is more than adequate and far more elegant than an LED blast to the eyes at midnight.

Size: A Major Step Toward Everyday Wearability

Perhaps the most significant engineering decision Casio made with the PRJ-01 is what it did with the case dimensions. The PRJ-01 gets a significant size reduction, dropping from the 46mm of the PRJ-B001 to a solid 39.1mm with a resin case. Forty-six millimeters is a big watch by any standard. At 39.1mm, the PRJ-01 enters territory that is genuinely versatile — substantial enough to read as a sport watch, compact enough to disappear under a jacket cuff or wear to dinner without commentary.

Measuring 39.1 millimeters wide and 11.6mm thin, and more suitable for unisex use, the PRJ-01 offers a simple three-hand analog style; it's the watch you throw on for a hike, a campsite weekend, a rainy dog walk, or an everyday outfit where a chunky digital watch feels like too much. That's a coherent, honest product identity — and it's rarer than it should be in a segment where manufacturers habitually pile on features to justify price points rather than asking which features the buyer actually uses.

What It Signals About Pro Trek's Direction

The PRJ-01 isn't an anomaly. Read alongside the PRJ-B001's simplification of 2024 and the broader category trend toward analog-adjacent outdoor tools, it represents a deliberate repositioning of at least part of the Pro Trek lineup. Casio is a company large enough to serve multiple audiences simultaneously, and nothing about the PRJ-01 suggests the sensor-laden PRW-6900 or the Bluetooth-equipped PRW-B1000 are going anywhere. But the brand appears to be acknowledging something that independent outdoor gear reviewers have been saying for years: the most technically capable watch isn't always the right watch for the trail.

The PRJ-01 also demonstrates that solar analog watches can be compact and genuinely lightweight. At 32 grams, it replaces the PRJ-B001 as the lightest Pro Trek watch ever made — a meaningful engineering achievement given that it still maintains 100-meter water resistance, a mineral crystal, and a solar-powered movement inside a case that measures just 11.6mm at the lug. The physical package is tighter and more refined than anything Casio has produced in this outdoor segment before.

Whether the American market responds the way Casio hopes will depend partly on how the brand positions the PRJ-01 when it arrives domestically. Market it as a budget watch and buyers will compare it against cheap field watches and find the resin construction off-putting. Market it as a trail-ready analog tool for the hiker who already has everything else they need and knows it — and the $157 to $194 price point becomes one of the cleanest value propositions in the outdoor watch space. The watch itself is ready. The story just needs to be told right.