If you plan to join the conference in Chiang Rai, it is recommended you make your flight reservations as soon as possible. This is because the conference will take place at the same period of Thailand’s big festival, Loy Krathong. Chiang Rai is one of the most popular provinces renowned for this festival. Therefore, the air fares can be much higher based on the law of supply and demand.

Don’t confuse Chiang Rai with Chiang Mai when you book your flights. Both provinces are located in the north close to each other, but Chiang Rai is the northernmost province in Thailand.
The airport code for Chiang Rai is CEI. The airport code for Chiang Mai is CNX.
The airport codes might help you distinguish these two similar provinces more easily.

One more thing, when you arrive in Bangkok, please note that there are two airports:
1. Suvarnabhumi International Airport (BKK), which is Thailand’s major airport.
2. Don Mueang International Airport (DMK) which serves as a secondary hub for low-cost flights, both domestic and international destinations.

It takes around 1 to 1.30 hours by car between these two airports. When you make a reservation for your flight from Bangkok to Chiang Rai (about 1.15 hours), please ensure that you choose the right connecting airport in Bangkok.
For example, if the flight from your home city arrives at Suvarnabhumi International Airport (BKK), you should look for a connecting flight departing from Suvarnabhumi International Airport (BKK) to Chiang Rai. This is because you can choose to travel from Bangkok to Chiang Rai at both airports in Bangkok. However, most international major airlines (except low-cost ones) will arrive at Suvarnabhumi International Airport (BKK).

Chiang Rai, about 785 kilometers from Bangkok, offers several transportation options for reaching and navigating the city. It's accessible by private vehicle, public bus, or airplane, though there's no direct train service.
Train: Direct train service is unavailable. You can take a train to either Lampang or Chiang Mai, followed by a bus journey of a few hours to Chiang Rai. You must travel to Lampang or Chiang Mai first, then catch a bus to Chiang Rai. Contact the State Railway of Thailand for more information. (State Railway of Thailand: https://www.railway.co.th/Home/Index).
Bus: Buses from Bangkok's Northern Bus Terminal take about 9 to 11 hours.

The province is pedestrian-friendly, supplemented by Grab taxi, Tuk-Tuks, Songthaews (minibus), tricycles, and a few taxis. To explore rural areas, local buses and Songthaews are options, but renting a car or motorbike offers greater flexibility. Rental agencies provide various options, though it's important to check insurance coverage. Motorbike rentals require caution and adherence to Thai traffic laws, including mandatory helmet use.