Hello! That sounds like an exciting trip. Here are some essential travel tips for your visit to Barcelona, Madrid, and Seville.

Best Time to Visit:
The best time to visit these Spanish cities is in spring (April to June) or fall (September and October). The weather is pleasant and these periods avoid the peak tourist season, ensuring less crowd.

Route and Accessibility:
You can reach Barcelona via direct flights from many major international cities. From Barcelona, you can take high-speed AVE train to Madrid, and then to Seville. Within the cities, there are reliable public transportation systems, including buses, trams, and metros.

Accommodation and Booking:
Booking in advance is recommended, especially during peaks season. All three cities offer a wide range of accommodations from luxurious to budget hotels. Airbnb are also available in these cities.

Clothing and Essentials:
Pack comfortable clothing suitable for mild weather. Spanish people are stylish, so you might want to include some nice outfits. Walking shoes are a must as you'll walk a lot, especially in Barcelona. Don't forget sunscreen, hat, and a good camera.

Health and Safety:
Spain is typically safe but be aware of pick-pockets in tourist areas. Spain has a very good health system, but travel insurance for health emergencies is recommended.

Local Etiquette and Respect:
Spanish people appreciate when tourists try to speak at least a few words in Spanish. It's customary to greet with a kiss on both cheeks. Remember to respect local customs and traditions at places of worship and historical sites.