Sure, It's exciting that you're planning to visit Romania's Iasi, Bucharest and Timisoara. Here are some practical travel tips for your trip:

Best Time to Visit:
The best time to visit these cities in Romania is during April to June and September to October, due to mild weather. The summer months are also suitable but may be crowded.

Route and Accessibility:
The most prevalent ways to travel between these cities are by train or by car. If you want to save time, domestic flights are also accessible.

Altitude and Acclimatization:
These cities are at low altitude so altitude sickness shouldn't be a concern. However, as always when traveling, it's essential to listen to your body and not overexert yourself.

Accommodation and Booking:
Book your accommodation in advance. There are a variety of options available from budget hostels to luxury hotels in all three cities. Some recommended areas in Bucharest are Old Town and the Palace of the Parliament. In Timisoara, look near Unirii Square and Theresia Bastion.

Clothing and Essentials:
Depending on the time of your visit, prepare to pack accordingly. Summers can be warm, so light clothing is fine but also carry a jacket for the evenings. For winters, layering is key along with gloves, hats and scarves. Carry a travel adapter for your electronic devices as Romania uses Type F plug outlets.

Health and Safety:
Romania is overall a safe country, but as with any travel destination, pay attention to your belongings. Landmines are no longer an issue in Romania, and the health care system is sufficient if there's an emergency.

Local Etiquette and Respect:
Romanians appreciate it when visitors make an effort to speak a few words in Romanian. It is customary to greet with a firm handshake. Also, it's respectful to dress modestly when visiting churches or monasteries.

Enjoy the charm of these Romanian cities!