Certainly, I'd be happy to provide some travel tips for your visit to the spiritual cities of Varanasi, Prayagraj, and Ayodhya.

Best Time to Visit:
The ideal time to visit these cities is during the winter months, from November to February, when the weather is pleasant and comfortable for sightseeing.

Route and Accessibility:
Varanasi, Prayagraj and Ayodhya are well-connected by railways, roadways and airways. Varanasi and Prayagraj both have airports with flights from major cities.

Altitude and Acclimatization:
These cities are located in the northern plains of India and you won’t require any specific acclimatization.

Accommodation and Booking:
These cities have a wide array of accommodations ranging from budget to luxury hotels. It is always advisable to book your stay in advance, especially during peak pilgrimage seasons. Do check for the availability of clean water and hygienic conditions while booking.

Clothing and Essentials:
Pack light cotton clothes if you're visiting during summer and spring. However, do carry a few warm clothes as it can get chilly during early mornings and nights. If you are visiting during winter, pack woollen clothes. Don't forget your sunglasses, sun hats, and sunscreen.

Health and Safety:
Ensure you drink only sealed bottled water and eat at clean places to avoid health issues. Carry a basic first aid kit and any required personal medication.

Local Etiquette and Respect:
Respect the local culture and traditions. Dress modestly, particularly while visiting temples. Avoid photography where it is not allowed, and always ask for permission before taking pictures of the locals.