Absolutely, these Iranian cities have a lot to offer when it comes to history, culture and spirituality. Here are some travel tips to assist in planning your trip to Kashan, Shiraz and Mashhad:

Best Time to Visit:
The best time to visit Iran is during Spring and Autumn, specifically from April to June and Sep-Oct. Weather is pleasant during these months and ideal for sightseeing.

Route and Accessibility:
You can start your journey from Tehran, Iran's capital. Kashan is a 3-hours drive from Tehran. Shiraz and Mashhad are accessible via domestic flights from Tehran's airport.

Altitude and Acclimatization:
These cities are generally at low to moderate altitude, so acclimatization isn't a major concern. However, it's still advised to take a day of rest if you're feeling tired after your journey.

Accommodation and Booking:
You'll find a variety of accommodations from budget hostels to luxury hotels in these cities. Remember to book accommodations in advance. Also consider staying in historic houses in Kashan, it's quite popular among travelers.

Clothing and Essentials:
Iran is an Islamic Republic, so dress modestly. Women should wear a headscarf and loose fitting clothes that cover their arms and legs. Men should wear long trousers and long sleeved shirts. Carry a sun hat, sunscreen and refillable water bottle.

Health and Safety:
Standard vaccinations like Hepatitis A, Hepatitis B and Typhoid are recommended for travel to Iran. It's safe to travel but avoid consuming tap water. Bottled water is always a safer option.

Local Etiquette and Respect:
Iranian people are known for their hospitality. Be respectful towards the cultural and religious customs. Do not photograph people without their consents, especially inside the mosques.