Absolutely! Visiting these magnificent Chinese cities will be an unforgettable experience. Below are some travel tips:

Best Time to Visit:
The ideal time to visit Beijing, Nanjing, Shanghai, and Hangzhou is during Spring (April to June) and Autumn (September to October) when the climate is most pleasant. Avoid visiting during the national holidays such as the "Golden Week" (1st week of October) when these cities get incredibly crowded.

Route and Accessibility:
You can start your tour from Beijing, from where you can take a high-speed train to Nanjing. From Nanjing, it's a quick train ride to Shanghai and lastly, Hangzhou. There are also direct flights from Beijing to Shanghai or Hangzhou.

Altitude and Acclimatization:
These cities are located at low altitudes so acclimatization will not be an issue.

Accommodation and Booking:
Plenty of choices are available ranging from budget accommodations to luxury hotels. It is recommended to book your hotels in advance, especially during peak tourist seasons and around the Chinese New Year.

Clothing and Essentials:
The weather can be quite changeable, so bring light clothing and also warmer layers. Comfortable walking shoes are a must. Don’t forget to bring pollution masks for cities like Beijing and Shanghai.

Health and Safety:
Tap water in these cities is not recommended to drink. Always drink bottled water. Carry essential meds, first aid kit and any prescribed medications.

Local Etiquette and Respect:
Chinese people appreciate it if you address them with their title followed by their last name. If someone gives you their business card, accept it with both hands to show respect. When visiting temples, dress modestly and follow the local customs.

Also, it's important to have a translation app as English isn't widely spoken everywhere. Lastly, be aware of the Great Firewall, many western websites and apps are blocked so you might want to consider getting a VPN.