Hiking from Eggishorn to Bettmeralp is a great moderately difficult hike with incredible views of the Aletsch Glacier and surrounding mountains as well as a few alpine lakes and ice caves. This hike is a good choice for adventurous families or single hikers on vacation.
To begin the hike, either drive or take the train to Fiesch. From the train station you'll need to walk about 15 minutes to the valley cable station. Take the cable car up to Fiescheralp and then to Eggishorn. The cable car isn't cheap, but the views are spectacular. (Note: Fill up your water before you get on the cable car! There's no free potable water at the top.)
At the Eggishorn mountain station there is a small restaurant and a viewing platform. This is where the hike begins. Follow the yellow hiking sign up to the summit of Eggishorn, which is only a quick 15-minute hike. The summit has fantastic views of the glacier with views stretching to the Jungfrau and further. To the south you can see the Matterhorn on a clear day! When you're done at the summit, turn around and head back to the mountain station.
From here, follow the yellow hiking sign down the mountain toward Tällisee and Märjelen-Stausee. At about 0.6 miles from the mountain station, turn left at the sign and continue toward Tällisee. Shortly after Tällisee, turn left at the sign to head toward Märjelen (the lake will be visible below in the valley). At the lake, turn left and head toward the glacier.
When you see the sign to head to the glacier, turn right and follow the trail. It's a bit steep in spots, but the hike only takes about 10 minutes. When you reach the glacier, be sure to walk down close and look at the deep blue ice caves. There is also a much larger snow/ice cave on the southern side of the valley. This is one of the only places in Switzerland that an official hiking trail actually reaches a glacier (the other glacier trails are all alpine/mountaineering paths).
It goes without saying, but be extremely cautious walking near and on the glacier. Many tourists walk up onto the glacier, but be aware that this can be very dangerous without the proper gear and guides! Use caution.
From the ice cave, continue along the trail toward Roti Chumma and Biel. This part of the trail leads gradually uphill for about 3 miles. When you reach Hohbalm, you can customize your trip a bit. If you wish, you can hike to the summit of Bettmerhorn, which has great views of the glacier. You can also hike down to Chatzulecher, which gets you quite close again to the glacier (though it requires a lot of elevation loss/gain).
After these trips you can follow the signs toward Bettmeralp. The hike leads down a grassy switchbacking path, and only 10 minutes after leaving Hohbalm, the village of Bettmeralp will come into view, with the Bettmeralpsee just above it.
When you reach Bettmeralpsee, follow the signs along the road to the cable car station. There are plenty of places to fill up your water (and get food) in Bettmeralpsee. When you are ready to leave, take the cable car back down to the Betten train station.
A few final notes: You can, of course, avoid using the cable cars by hiking up and down instead. However, the hikes are strenuous and may be too long to fit into a day hike. One doable modification is to take the cable car to Fiescheralp instead of Eggishorn and hike the rest of the way. See Fiescheralp to Eggishorn Hike for more info.