What is the fine-grained topic of the following text: Leaving Chiang Mai by bus at 9am in the morning it is possible to reach the Thailand / Myanmar border at Mae Sai / Tachilek by lunch time, and be back in Chiang Mai with a newly activated Thailand entry stamp in time for a late nights dinner, providing only a couple of hours is spent wandering the labyrinth of street stall that comprise the Tachilek market. Only return the topic.
Traveling from Chiang Mai to the Thailand / Myanmar border at Mae Sai / Tachilek and visiting the Tachilek market.