If you are looking for a tour of Castner Glacier, please see the Castner Glacier Winter Tours page.

September 11, 2026 Update:

A significant stream flowing along the south edge of the glacier has increased in flow this summer and has made it impractical to reach the ice cave or get a good view inside by hiking up the south side of the creek when the water level is high. Water levels are decreasing now due to colder weather so it is possible to hop the stream again, but until the creek freezes over later this winter (probably around early November) hikers should follow the north side of Castner Creek to the glacier if they want to avoid potentially getting their feet wet. The water flowing out of the ice cave has carved away some of the bank around the first bend in the creek downstream of the cave and the water is now flowing through areas that have been dry for the past few years, so the final approach to the ice cave is a little different and you may have to scramble over some small hills to get around the water. There is also a new & very gnarly rapid in the creek downstream of the cave that would be dangerous to anyone who accidentally falls into the creek, so be careful not to go sliding down the ice outside the cave entrance. There is also a new hole in the ceiling of the ice cave inside on the right side where the “alcove” has been for several years. It may look tempting to slide down into the cave through the hole right now, but it would be very difficult or perhaps impossible to climb back out unassisted, and the ice around the hole may still be unstable. Later this winter the hole will be cool feature inside the ice cave, at least until a snow drift buries it.

Yes, the ice cave at the front of Castner Glacier still exists and did not collapse as many people around Fairbanks currently misunderstand! The very front portion of the cave recedes as it melts during each summer and may suffer minor partial collapses occasionally as a result, but these partial collapses do not result in a significant reduction in the length of the cave. Reports about these minor partial collapses have been misinterpreted by many non-experts to mean the entire cave collapsed and no longer exists, which is not true. I’m there every week during winter, I should know! There are recent photos of the ice cave on my tour page.

The ice cave is not visible until you are standing in front of it now. It is located on the south corner of the glacier terminus where Castner Creek empties from the glacier.

General Advice For Hiking To The Glacier In Winter:

When the weather is nice, the trail is in good shape, and participants are adequately clothed & equipped with headlamps, the consequence of starting late may be low, though visitors won’t be able to see or photograph the ice cave well in the dark. However, in extreme cold/snowy/windy weather starting late is very dangerous. The trail can disappear quickly when the wind is blowing or heavy snow is falling and it’s harder to follow in the dark. If you lose the trail in the dark you will be lost without cell phone service and sinking in very deep snow as you struggle to find your way back to the highway, which is a great way to get frostbite or die of hypothermia. I personally stopped one group of highly unprepared tourists attempting to start their hike once in December after dark with no lights, snowshoes, face coverings, or any clue where they were going in a snowstorm with a -15°F wind chill. One of the people in this group even had an apparent exercise-induced asthma attack and required their inhaler. Please have respect for the extreme weather in the mountains and don’t try anything this brazenly stupid, because no one will likely be there to stop you or save you. Other tourists have suffered frostbite on their faces while attempting the hike in -40 to -60F wind chills (-15F or lower temp with 20+ mph wind) because they did not properly cover their faces on the hike or understand the danger of a -40 wind chill, where frostbite can occur on exposed skin in 5-10 minutes. On nice weather days when the trail is packed, Castner can be mostly easy, and this is what the people who tell you it’s an easy hike experienced when they visited. But on bad weather days when the trail is snowed over it is an experts-only hike and beginner hikers or those without extreme cold weather experience should not attempt it on their own. Imagine getting lost in the dark in snow up to your waist while your fingers, toes, and face are freezing because you went out without the proper gear for subzero weather, your cell phone doesn’t have any service, and you suddenly need your inhaler but you left it in the car or you dropped it in the snow while you were stumbling around in the dark. C’MON! You can literally die in conditions like that, let alone lose some fingers and toes!

Once Castner Creek has frozen over near the ice cave in late October/early November, please hike up the SOUTH side of the creek throughout the rest of winter and do not walk across the bridge as doing so is quite dangerous. DO NOT follow directions on AllTrails or other sites that indicate you should follow the north side of the creek as there is no parking or trail on that side in winter. ALWAYS test the ice before each step when crossing Castner Creek with a hiking pole, axe, or other tool—you are most likely to encounter thin ice in the middle of the creek where you may also hear the water rushing beneath you. If there is a packed trail in the snow, stick to it to avoid sinking in deeper snow or breaking through the ice on Castner Creek. There are many spots along the creek which remain unfrozen or only covered by thin ice, and some of these holes may be bridged by snow. Falling in the creek can be quite dangerous in extreme cold where frostbite or hypothermia may quickly ensue. If you visit while it is snowing or shortly after heavy snow has fallen and there is no trail to follow, you will struggle to find the ice cave unless you have been there before or are an experienced winter Alaska explorer. I have observed many self-guided groups fail to reach the cave both due to the difficulty and due to starting late, while many who made it struggled heavily because the trail was not solidly packed and they did not have snowshoes. The floor of the ice cave never freezes deep in the back of the cave, so expect to find open water and thin ice as you push deeper into the cave. Running water can usually be clearly heard and seen with a bright light. Bring headlamps or bright flashlights if you want to explore inside the cave—phone flashlights do not illuminate very well and phone batteries often drain in the cold, especially older phones. In fact, you should always have a headlamp when hiking in case you run late and find yourself still hiking in the dark. The ice cave is prone to overflow, where new ice that forms during extreme cold restricts the flow of the water in the cave, causing it to back up and overflow on top of the old ice, but typically there will only be a few inches of water on top of existing ice when this happens. However, overflow can build up in low spots and be deep enough to submerge your boots. Overflow also occurs in places along Castner Creek, especially closer to the ice cave, so beware anytime you see wet spots or fresh ice with no snow on top in the middle of winter as there is probably water lurking under the adjacent snow. Budget at least 2 hours before sunset for your hike. The drive usually takes 3+ hours in winter, longer than Google Maps will predict because most groups will stop for a break in Delta Junction and in a few spots for photos, and bad weather or icy roads may slow you down. It is completely dark by 4pm near the winter solstice (Dec 21) and dark by 5pm or so from roughly Thanksgiving to late January.

If you are planning to visit in winter, note that conditions and difficulty will vary considerably month-to-month as freeze-up occurs and snow accumulates, but also day-to-day depending on the weather. If you are parking on the south side of the Castner Creek bridge, DO NOT CROSS THE BRIDGE as it is very dangerous! Watch for traffic (especially big trucks traveling 65mph!) as you walk from the parking area to the bridge and stay out of the road. In good weather, you will usually find a packed trail in the snow leading to the ice cave, though the trail may be confusing to follow due to diverging tracks left by others and lack of signage. Be advised that during or shortly following snowy or windy weather these tracks will disappear under snow. Breaking trail to the cave is very difficult without snowshoes and potentially dangerous if you fall in a hole concealed by snow along Castner Creek — I don’t recommend doing so unless you are adequately prepared and know exactly where you are going. (I am quite often the person who breaks in the trail after snowstorms.) Always avoid low spots & sagging snow in the creek and do not navigate along the middle of the creek—stick to the extreme edge and keep your distance from open water. I have seen many groups fail to reach the ice cave on bad weather days and I’ve watched many others struggle heavily without snowshoes when trail conditions were poor. Check the weather for “Black Rapids, Alaska” before you go and view driving conditions for the Richardson Highway on 511.Alaska.Gov from Mile 266 in Delta Junction to Mile 218 at Castner Creek to ensure the highway is not closed or hazardous. The hike is 1.25 miles each way and takes an average group at least 40 minutes each way in GOOD conditions, so do not attempt to hike to the cave less than two hours before sunset. In POOR conditions, the hike may take well over an hour each way and the trail may disappear under snow on your return hike if a strong wind is blowing or heavy snow is falling. I see people almost every day between November and early March attempting to start the hike late and many turn around without reaching the cave or they get lost in the dark on their return, so don’t be like them! If you are overweight and sedentary, you will struggle heavily on this hike even when trail conditions are good, and if you are also near 60 years of age or older you may not be able to complete it. (“Sedentary” is the main factor. If you haven’t walked 3 miles in the past few years, don’t expect to easily walk 3 miles through snow in the cold.) If you are not adequately dressed for the cold, you are risking frostbite and hypothermia, especially when wind chills are below zero degrees F. Always bring extra layers and dry socks. I don’t recommend bringing infants or toddlers to the cave who cannot walk themselves when the temperature or wind chill is below zero degrees F (-18C) since they will have trouble staying warm and may not be able to communicate adequately if their fingers or toes are freezing. (Experienced parents from Interior Alaska excluded.) Please note that deep inside the ice cave the temperature remains constant near freezing, so it may serve as an emergency warming shelter even when the temperature outside is well below zero F. Cell service is not reliable along Castner Creek (or anywhere in the mountains if you have Verizon) and the nearest emergency services are located one hour away, so be prepared to take care of yourself.