What one-day trips are available from Zurich (Switzerland)?

One of my favorite places in Switzerland is Interlaken. The are is beautiful and you can take a short train ride up to Kandersteg for some beautiful waterfalls and a great mountain hike. It is a 2 hour train ride. Interlaken is known as the extreme sports capital of Switzerland. You can skydive, canyoneer, or mountain climb.

Kandersteg:

Another option is Lucern. Lucern is a wonderful city with a interesting old city wall running through it. It also has many other things to see and do.

My last recommendation would be Bern. Bern is the capital of Switzerland. It has some really cool historical buildings and plenty of things to see including the capital buildings.

If you like science I'd recommend the Technorama (Swiss Science Center). It's located in Winterthur. So it's very close to Zürich. Most instructions are available in English.

http://www.technorama.ch/en/

I live in Bern and we have a yearly tradition: The Zibelemärit. From Wikipedia:

The Zibelemärit (Bernese German dialect; English: Onion market) is an annual market with aspects of a fair in the old town of Berne, Switzerland. It takes place on the fourth Monday of each November.

Historical research indicates that the Zibelemärit originated in the 1850s with marmettes, farmer's wives from around Murten, coming to Bern at around St. Martin's Day to sell their produce. However, a persistent local legend holds that the Zibelemärit is a much older festivity. According to this legend, the Bernese awarded the people from the nearby city of Fribourg the right to sell onions in the city in reward for their aid after a fire destroyed much of Bern in 1405.

As the name indicates, it is mainly onions that are sold on the Zibelemärit. Bernese farmers, who are proud of their decorative onion tresses and onion wreaths, also sell other onion products at the market, including Zwiebelkuchen (onion pie), onion soup and onion sausages. Decorative chains of sugar onions are also popular with children.

The Zibelemärit opens very early in the morning, at around 03:00 to 04:00. Later in the morning, the narrow alleys are usually packed tight with people, which is what the Bernese call the Gstungg. A general confetti battle in which mostly children participate ensues at four o'clock in the afternoon, officially ending the market.

You can go to Konstanz in Germany. It is about one hour from Zurich by car or train. It is a rather cosy city and life is less expensive there than in Zurich.

You can also go to Friedrichshafen, visit the Zeppelin Museum and, if you are looking for something special, you can have a sightseeing flight with a dirigible.

Driving to Lake Lucerne have a look and go on to reach the Grimsel Pass. I like doing this by car or motorbike.

Another day trip would be Rhine Falls near Schaffhausen, which is the largest plain waterfall in Europe.

We were there in January, so we did one day skiing (Flumserberg seems to be the place of choice for most locals, although you can google a few other resorts within 1h-1.5h by train). If you don't have a car, then the cheapest way is to buy Snow'n'Rail package (train + skipass) at the train station.

We also went to Lucern, which is really nice. There is a bit of old town, cruises on the lake (although we didn't have time).

Zurich is very nicely, centrally located, in Switzerland, both within the country itself, and in relation to neighboring countries.

It's about three hours from Geneva, in the French part of the country. Another two hours or so will take you to Lyons, the second largest city in France.

Likewise, it's a couple hours to Locarno, near the Italian border, and a couple hours more will take you to Milan, Italy.

Going to Vienna, or parts of eastern Austria in a day is a "stretch," but there are some major cities in the west such as Innsbruck, with churches and cathedrals, that are within reach. Lichtenstein, and its capital Vaduz, is also on the way.

And parts of southern Germany, such as the Black Forest, or Lake Constance, within a two or three hour radius, with Munich a bit further beyond Lake Constance.

I'd go to Liechtenstein and hike the Fürstensteig. No different than hiking in Switzerland, but it's fun to visit such a small country.