Hello! It's great to hear that you are planning your visit to Heredia, Cartago, and Alajuela. Here are some travel tips that might help you during your visit.

Best Time to Visit:
The best time to visit Heredia, Cartago, and Alajuela in Costa Rica is from December to April, during the dry season. However, please note the country has a tropical climate, so it might still rain occasionally even during the dry season.

Route and Accessibility:
Juan Santamaría International Airport is the closest international airport to all three cities. From the airport, you can hire a shuttle bus, taxi, or rental car to reach your desired city. Buses are affordable and travel frequently between these cities.

Accommodation and Booking:
Various types of accommodations are available in these cities from budget homestays to luxury resorts. You can make your booking in advance via popular hotel booking websites. Casa Primo (Heredia), Mountain Paradise B&B (Cartago) and Hotel Los Volcanes (Alajuela) are some recommended places.

Clothing and Essentials:
Considering the tropical climate, lightweight clothing made of breathable fabrics are recommended. Always carry a light raincoat or umbrella, sunscreen, bug repellent, water bottle, and sturdy shoes for walking or hiking.

Health and Safety:
Costa Rica is generally safe. However, exercise normal security measures. Stay hydrated, especially in hot weather. Carry a first aid kit for minor injuries. If you plan on hiking, it's safer to go with a guide. Also, check with your healthcare provider about any recommended vaccinations.

Local Etiquette and Respect:
Costa Ricans, or Ticos, are known for being friendly and polite. When greeting, a firm handshake is usual. Tipping is generally included in your bill at restaurants, but it's customary to leave small change. Respect local culture and the environment, especially if visiting national parks or nature reserves.