Chumphon Archipelago is in Thailand and includes the coast of the Provinces of Chumphon and Surat Thani on the Kra Isthmus and the islands of the Gulf of Thailand of Koh Tao, Koh Samui, Koh Phangan and the islands of Mu Ko Chumphon National Park
The Chumphon Archipelago is a tourism zone that covers two regions, the provinces of Chumphon and Surat Thani on the Kra Isthmus and the islands of the Gulf of Thailand of Koh Tao, Koh Samui, Koh Phangan including the Mu Ko Chumphon National Park 
Cities located in the Archipelago include the towns of Chumphon, Surat Thani, Chaweng on Koh Samui.
The Chumphon Archipelago is a key tourism zone in Thailand and increasingly popular with the numerous air and boat connections between the mainland and the islands of the Gulf if Thailand. It is an Eco tourism destination and has diversified natural resources which is very important in the term of genetic sources of wildlifes and knowledge for studying and research.
Beach forest: This forest type is characteristic of the more exposed beachfronts around the coast of Thailand and is dominated by Casurina tree (Casuarina equisetifolia), Terminalia catappa and Derris indica etc.. Due to the severe waterstress occurring above the beach zone the tree density and total species diversity in beach forest is low when compared to other forest types. This forest type has a moderately rich bird fauna.
Limestone forest: occurs on the exposed cliff faces and in the very shallow soils on top of the limestone hills and in many of the islands. Most of the plants found here are small and highly adapted to survive in this severe environment which is lack of nutrient and water. The dominant species are Ficus sp., Dracaena loureiri and Euphibia antiquorum etc..
Mangrove forest: Mangrove forest is an evergreen forest type. It is restricted to the area where freshwater and seawater mix and where the land meets the sea. It can not survive in pure freshwater or pure seawater. This forest type occurs in sheltered locations such as the mouth of streams and rivers flowing into the sea and especially in estuaries. This forest type provides good habitat for young aquatic fauna as a nursing ground, reduce hazard from strong wind and big wave, filtering pollutants in the water and also habitat for many kinds of animals e.g. crab-eating macaque, monitor lizards, birds, mollusk, fish etc. The common species found here are Rhizophora apiculata, R. mucronata, Bruguiera cylindrica, B. parviflora and Ceriop tagal etc.
Via Chumphon Airport (CJM) Located 30km north of Chumphon city in Pathio District . It has three direct daily flights connections with Bangkok's Don Meuang Airport (DMK) . Flights from Bangkok are around 60 minutes. High-speed Lomprayah  catamarans depart from Chumphon to Koh Pha Ngan. Nok Air  operates the three daily flight between Bangkok (Don Mueang - DMK) and Chumphon Airport, Pathio District, Chumphon (CJM). Nok Air offer a combined flight and ferry ticket on their website to Ko Tao and other islands. Transit agents in the arrivals hall can arrange onward connecting travel to the islands of the Koh Tao, Koh Phangan. The TAT or Tourism Authority of Thailand, Chumphon has a tourism information counter at the airport offering information on the region.
Via Koh Samui Airport (USM) Koh Samui which has frequent flights from Bangkok and Phuket, daily flights from U-Tapao and Singapore, and several direct flights each week from Chiang Mai and Kuala Lumpur. Transportation to the ferry dock is easy to find at the airport. Ferries depart several times a day with the last one around dusk. Flying via Ko Samui is generally more expensive than via Surat Thani or Chumphon Airport.
Via Surat Thani Airport (URT) The next nearest airport is Surat Thani on the mainland. Flights from Bangkok are generally cheaper than if flying to Samui , as there are low-cost carriers Thai AirAsia flying there, even Thai Airways charge 30-50% less than to Samui. However, you'll then need combined bus + boat travel to get to Ko Pha Ngan, which will surely take several hours. AirAsia uses the old airport in Bangkok, Don Mueang, while Thai Airways uses the international airport, Suvarnabhumi. Nok Airways sell a combined package ticket including airfare to Surat Thani or Nakhon Si Thammarat, bus ride to the pier, and a ticket on the Lomprayah high-speed catamaran.
Three main operator run ferries and high speed catamarans in the Chumphon Archipelago being Lomprayah, Songserm and Seatran.
From Ko Samui: There are at least ferries a day from Ko Samui's "Big Buddha" pier directly to Ko Phangan and Surat Thani. Ferries also leave from Nathon and Mae Nam piers to Thong Sala several times a day. Fast Lomprayah catamaran and Songserm Express. Scammers at [Ko Samui] airport who try to sell you a bus/boat combo for an exorbitant price. Make sure to walk towards the exit of the airport where there is an Information counter and taxi stands.
From Ko Tao and Chumphon: There are fast Lomprayah catamaran operating twice a day to Ko Tao for 450 baht at 08:30 and 13:00 or leaving Koh Tao for Ko Pha Ngan at 09:30. The ride between these islands takes 1.25 hours. A cheaper, but slower ferry operates from Ko Pha Ngan to Ko Tao by Songserm express and costs 350 baht, leaving Ko Pha Ngan at 12:30, and takes 1.5-2 hours.
From Surat Thani: night ferry leaving at 23:00 from Surat Thani city (walking distance from bus stations Talat Kaset 1 and 2) arrives at Thong Sala pier-[Ko Pha Ngan] at 06:00 and costs 400 baht for a space on a mattress on the boat. The night ferry leaves from Thong Sala-Ko Pha Ngan for Surat Thani at 22:00 for 400 baht arriving around 05:00-06:00. Songserm Express boat from Surat Thani city or train station including bus transfer costs 350 baht and takes around 3.5 hours.