Vienna

1. Schönbrunn Palace: A UNESCO World Heritage site, this baroque palace with its extensive gardens and the world's oldest zoo is a must-visit.
2. Hofburg Palace: The former imperial palace now houses several museums, the Spanish Riding School, and the Austrian National Library.
3. St. Stephen's Cathedral: An architectural marvel and one of Vienna's most important Gothic structures.
4. Belvedere Palace: Famous for its extensive art collection, including works by Gustav Klimt.
5. Vienna State Opera: A premier opera house with world-class performances.

Salzburg

1. Hohensalzburg Fortress: Overlooking the city, this fortress offers panoramic views and a glimpse into medieval life.
2. Mirabell Palace and Gardens: Famous for their beautifully landscaped gardens and the "Sound of Music" filming locations.
3. Mozart's Birthplace: A museum dedicated to the life and works of the famous composer.
4. Salzburg Cathedral: A stunning baroque cathedral in the heart of the city.

Innsbruck

1. Innsbruck's Old Town: Features landmarks like the Golden Roof, a 15th-century building with a gilded balcony.
2. Nordkette Cable Car: Takes you from the city center to high alpine terrain in just 20 minutes.
3. Ambras Castle: A Renaissance castle with impressive art collections and historical artifacts.

Natural Attractions

1. Grossglockner High Alpine Road: A scenic route offering stunning views of Austria’s highest mountain, Grossglockner.
2. Lake Wolfgang (Wolfgangsee): A popular lake for water sports and surrounded by picturesque towns.
3. Hallstatt: A UNESCO World Heritage village known for its stunning lake and mountain scenery.
4. Eisriesenwelt Ice Cave: The largest ice cave in the world, located near Werfen.

The Austrian Alps

1. Tyrol Region: Famous for skiing resorts like Kitzbühel and St. Anton, as well as summer hiking.
2. Zell am See: A beautiful alpine town with a crystal-clear lake, popular for both winter and summer activities.
3. Stubai Glacier: One of the largest glacier ski resorts in Austria.

Cultural and Historical Sites

1. Melk Abbey: A baroque masterpiece overlooking the Danube River.
2. Kreuzenstein Castle: A medieval castle near Vienna, known for its well-preserved architecture and falconry displays.
3. Mauthausen Memorial: A former concentration camp, now a memorial and museum.

Wine Regions

1. Wachau Valley: A UNESCO World Heritage site known for its high-quality white wines and beautiful landscapes.
2. Burgenland: Famous for its red wines and the Neusiedler See, a large shallow lake ideal for birdwatching and water sports.

Danube River

1. Danube River Cruises: Offer scenic views and stops at historic towns such as Dürnstein, where Richard the Lionheart was imprisoned.
2. Linz: Known for its vibrant arts scene and the Ars Electronica Center, a museum of the future.

Adventure and Outdoor Activities

1. Hiking and Cycling: Extensive trail networks in regions like the Salzkammergut and the Hohe Tauern National Park.
2. Paragliding and Skydiving: Popular in alpine areas for stunning aerial views.
3. Water Sports: Lakes such as Wolfgangsee and Neusiedler See offer opportunities for sailing, windsurfing, and more.

Unique Attractions

1. Hundertwasser House: A colorful and unconventional residential building in Vienna designed by artist Friedensreich Hundertwasser.
2. Prater Park: Home to the famous Giant Ferris Wheel, offering panoramic views of Vienna.
3. Riegersburg Castle: Located in Styria, this castle offers a glimpse into medieval life and breathtaking views of the surrounding countryside.

Austria’s diverse attractions make it an appealing destination for travelers with varied interests, from history buffs and culture enthusiasts to nature lovers and adventure seekers.