With the travel duration to Thailand around 18 days, there are many nice trip you can do, we have several sample itineraries from classic tours to trekking tours, cycling tours , beach holiday. You can find all here in the list of Thailand tours 18 days
Kanchanaburi - Sukhothai - Ayutthaya - Bangkok - Chiang Mai - Chiang Rai - Chiang Saen - Luang Prabang Private
Ayutthaya - Bangkok - Chiang Mai - Krabi - Phnom Penh - Sai Gon - Can Tho - Chau Doc Private
Bangkok - Chiang Mai - Krabi - Hanoi - Halong Bay - Sai Gon Private
Kanchanaburi - Ayutthaya - Bangkok - Chiang Mai - Chiang Rai - Koh Lanta Private
Kanchanaburi - Bangkok - Chiang Mai - Chiang Rai - Chiang Saen - Phuket Private
Ayutthaya - Bangkok - Chiang Mai - Chiang Rai - Ko Phi Phi - Kuala Lumpur - Singapore Private
Sukhothai - Ayutthaya - Bangkok - Chiang Mai - Luang Prabang - Vang Vieng - Chiang Khong Private
Bangkok - Chiang Mai - Chiang Rai - Koh Lanta - Krabi - Khao Sok Private
Ayutthaya - Bangkok - Chiang Mai - Hanoi - Halong Bay - Siem Reap - Sai Gon Private
Ayutthaya - Bangkok - Chiang Mai - Chiang Rai - Chiang Saen - Luang Prabang - Vang Vieng - Vientiane Private

We had chosen an excursion with a Francophone guide. Whose name is dom? And the driver's name was Tony. Both of them have been inc...
We had a ball in Bangkok. Phuong Ivy Ha took care of all our needs from transportation to flights. She really made this trip so aw...
I thank Lan CHU of Thai Unika for his patience in developing our 18-day tour. We come home with incredible memories thanks to you...