That sounds like an exciting trip! Austria is a beautiful country with lots to offer, from Vienna's vibrant art and music scene, to Salzburg's impressive baroque architecture, and Eisenstadt's rich history.

Best Time to Visit:
The best time to visit these Austrian cities is from April to June or from September to October when the weather is mild and pleasant. However, if you are a lover of winter sports, December to March can also be a great time to experience the country's wonderful ski resorts.

Route and Accessibility:
Flying into Vienna International Airport would be the most convenient. From there, you can easily access the city centre via train, bus or taxi. For onward travel to Salzburg and Eisenstadt, the Austrian Federal Railways offer regular, reliable services; alternatively, car rentals are widely available.

Accommodation and Booking:
Booking.com, Airbnb, and local hotel websites provide a wide range of accommodation options to suit different budgets. It's advised to book well in advance, especially during high tourist season and around major holidays.

Clothing and Essentials:
Pack warm clothing if you plan to visit in winter, as temperatures can be very cold. During the warmer months, light clothing is suitable, but also pack a waterproof coat for unexpected showers. Comfortable walking shoes are essential as the cities are best explored on foot. Don't forget an adapter for European power outlets.

Health and Safety:
Austria is generally very safe, but it's always advisable to have comprehensive travel and health insurance. Tap water is safe to drink. Make sure you have necessary medications and check with your local health department for any specific vaccinations you might need before travel.

Local Etiquette and Respect:
Austrians value punctuality and politeness. When entering shops or restaurants, it's customary to greet with 'Guten Tag' or 'Grüß Gott'. Tipping is also customary in restaurants and for service staff.