Sure! San Cristóbal, Mérida, and Trujillo are beautiful cities in Venezuela, each with its unique charm. Here are some travel tips:

Best Time to Visit:
The best time to visit these cities in Venezuela is during the dry season, which lasts from December to April when the temperatures are comfortable and skies are clear.

Route and Accessibility:
You can directly fly into the cities from Caracas, the capital of Venezuela. Public transportation such as buses and taxis are generally available and cabs are the most convenient for intercity travel.

Altitude and Acclimatization:
San Cristóbal sits at an altitude of about 860m, Mérida at 1,630m and Trujillo at 800m. Acclimatization should not be an issue for most travelers at these altitudes.

Accommodation and Booking:
Several types of accommodations are available, including hotels at different price points, hostels, and rentals. Booking in advance is recommended, especially in peak tourist season.

Clothing and Essentials:
In general, clothing that is suitable for a warm climate is appropriate. However, nights can get chilly so also pack light sweaters or jackets. Don't forget to bring a good sunscreen, insect repellent, and a hat for sun protection.

Health and Safety:
International travelers are recommended to have a yellow fever vaccination. Follow food safety measures, as poor sanitation can be an issue. Also, be aware of your belongings as petty theft can be a problem.

Local Etiquette and Respect:
Venezuelans are known for their warmth and hospitality. When meeting someone for the first time, a handshake is common. Most Venezuelans are Catholic, so when visiting churches, dressing modestly is advised. Also, tipping in restaurants is customary and usually around 10% of the bill.

Do note that Venezuela has been experiencing socio-economic instability in recent years, so it's crucial to monitor local news, remain vigilant, and consult local advice before your trip.