24-Hour Layover in Helsinki

Checkout this mini-guide: http://en.wikivoyage.org/wiki/Helsinki Helsinki is a small city, so it's easy to see a lot in one day.
The highlights include the Rock Church, Luthern Church, a Russian Orthodox church, and the Suomenlinna fortress which is a UNESCO world heritage site.

Go down to the harbor market for lunch. The merchants sell some interesting and quite tasty dishes. Pretty cheap too. I was a little less than overwhelmed by Suomenlinna, but I can think of far worse ways to spend a few hours. Of if you like animals, the Helsinki zoo has a pretty good collection of big cats. You can catch the boat to the zoo from the harbor. I had an excellent seafood dinner at a nearby restaurant, but I can't remember the name. It was right by the indoor market, and looking at Google streetview, I think the name was G.W Sundmans Krog. PS- Finland is Nordic but not Scandinavian...

Helsinki is a new city, it started as a village to support the fortress. Don't expect to see a lot of "Old World" architecture or sights. I highly recommend the TI downtown as a first stop, they are one of the most helpful TI's I have ever visited. We enjoyed Suomenlinna Island, you can spend up to a half day there wandering the old fortress island. It's reached by a ten-minute boat ride from downtown. There are at least two companies that run between the island and downtown - make sure the line you're in is the same one you have a ticket for. Outside of the island, I suggest spending your day exploring the center area. We went to the Rock Church by tram but weren't really impressed. Unless contemporary architecture is a passion, it's probably not worth the trip. Another option is the open air museum. We didn't visit but it might interest you: http://www.tripadvisor.com/Attraction_Review-g189934-d202598-Reviews-Seurasaari_Open_Air_Museum-Helsinki_Southern_Finland.html

A full day is plenty of time to get a nice taste of Helsinki, as others mentioned, it's a relatively small city easy to walk around. Don't miss the harbor and market area there. Lunch in the old market hall can be wonderful and pretty inexpensive. A great way to try Finish specialties like various smoked fish, reindeer meat, etc... The cathedral area is an absolute and has a great deal of Russian architecture similar to St. Petersburg (Helisnki was built by the Russians during Peter the Great's reign). There is also a Russian Orthodox church near the harbor (onion domes). The boulevard that leads away from the harbor is another must. In the park there is the glass and iron coffee shop that is a great place for a fancy coffee and pastry. The church in the rock is cool, if you do like modern architecture it is worth it. But it's more of a hike. The train station is one of the most important designs by Eliel Saarinen (who later moved to Michigan and is the father of Eero Saarinen). It is amazing Art Nouveau architecture. The TI can also direct you to other wonderful examples of Art Nouveau - there is a lot in Helsinki. Don't worry about language, English is well spoken and everywhere. As someone noted, Finland is technically not Scandinavian. If you can, taking a real Finnish sauna would be a memorable experience. But you must leave your modesty at home to do it...

Clearly I am ignorant of anything Scandinavian AND Nordic :) I will need to look up the difference between the two. But the info you have given so far is all very helpful! Thanks!

If you want to have a great view of this beautiful city go to the top of Sokos Hotel Torni. Stunning! You can just go for a drink and take wonderful pictures. I agree with what others said, you can visit the top 3 church in a day. I also liked the National Finnish museum since I did not know much about this country...it was a must for me! http://www.nba.fi/en/nationalmuseum

It depends on what you would like to see & what interests you. You will have VERY long days and hopefully the weather will be nice & warm when you are there. Anything from the low 50s to the low 90s is possible but the weather report in the days before you leave will tell you what kind of spring they are having this year. If it's nice I would walk around and look at things, if it's rainy & cold I'd book a bus tour of Helsinki. One thing that is never in the guide books and aAmerican vistors often like: peek around the corner from Uspenski catherdral at the north harbor. In summer the biggest icebreakers are often tied up there in front of the Admiralty offices. Pretty cool looking ships! The Omena Hotel http://www.omenahotels.com/ may be your cheapest overnight, rooms come with a small frig & coffee maker, complete w/ coffee, tea, creamer etc. There are 3 in HKI nowadays. Something I enjoy about summer in HKI is the huge outdoor pool at the Olympic stadium. The Stadium also has a hostel in it if you want want truely budget accommodations. Other than this it's hard to say what you would like w/o knowing what interests you. My mom would want to visit museums, I'd call the HKI Dive Centre and try to dive the Gustav Adolph (also a museum). To each his/her own.

Me again!! So we finally reserved our flights and we still have that 24-hour layour in Helsinki, only it's at the end of our trip instead of the beginning (July 31 - Agusut 1). Also, the times have changed. Instead of early-morning to early-morning, our flight arrives at 3:05pm on the 31st and leaves around 2pm on the 1st. Does that change things as far as your suggestions, since we probably won't get into the city until about 5pm and will have to leave to return to the airport around 11am the next morning? Thanks!