Here are a few pictures of the Chiang Dao Forestry Department.

This is the place to ask prior to hike up Doi Luang Chiang Dao.
An authorization needs to be asked at this office.

A guide and/or porter was compulsory in the past and probably still is for several reasons.
The main one is of course safety, but also to carry water as there isn't any source of water for hiking up and down and other needed advices or info..

The Doi Luang Chiang Dao is quite famous for having a few endemic species of plants and flowers..