Hello! That sounds like an exciting trip to Austria, visiting Salzburg, Vienna, and Eisenstadt. Here are some travel tips for your journey.

Best Time to Visit:
The best time to visit these Austrian cities is during the spring (April to June) and fall (September to October) when the weather is mild and pleasant.

Route and Accessibility:
You can easily reach Austria via numerous international flight connections. Once in the country, the public transportation is efficient and reliable. Trains connect Salzburg, Vienna, and Eisenstadt.

Accommodation and Booking:
All these cities offer a wide range of accommodation options from luxury hotels to budget hostels. It's advisable to book your accommodation in advance, particularly during peak seasons.

Clothing and Essentials:
Pack layers for your trip as weather can fluctuate. Essentials would include comfortable walking shoes, a good quality rain jacket and umbrella. Don't forget to pack a power adapter for your electronic devices.

Health and Safety:
No special vaccinations are required for Austria. However, European Health Insurance Card (EHIC) holders are entitled to state-provided medical treatment. Always ensure you have adequate travel insurance coverage.

Local Etiquette and Respect:
Austrians are generally formal and polite. When entering shops or restaurants, it is customary to greet with a 'Grüß Gott' (good day). Silence is valued in public transport. Tipping is generally expected in restaurants and for services.