The longest railway tunnel in Thailand is "Khun Tan Tunnel" between Lampang and Lamphun a province that was penetrating under Doi Nga Chang of the Khun Tan Mountain Range, with the length 1,362.05 meters before going through the other side. It is a miracle that happened in the reign of King Rama V, causing excitement for the whole country which requires a lot of science and perseverance because there is no tool like in this era; it takes a man's force to hammer one stone at a time. The commute to work was difficult. It had to invade the forest and carry equipment repeatedly, the German engineer who supervised all the work was also arrested as a "People of the Beast” it took up for 3 reigns to be able the car came in there. After King Chulalongkorn, Rama V initiated the construction of the railway on 4 March in 1891, until the end of 1905, the Northern Railway was only able to travel to Nakhon Sawan Station and exploring the route to reach Chiang Mai but there is a big obstacle, the Khun Tan mountain range that is blocked and difficult to avoid. After two years of exploring, it was finally decided to dig a tunnel through it as in Europe. But digging a tunnel under a kilometer long mountain like this and in the wilderness that had to climb mountains, It is the way that Thai people generally do not see a possible way but there is faith in German engineers. At that time, Thai people were very popular with Germans. It is said that German products are of better quality than all nations in the world. They are still in a relationship with each other comfortably because the Germans had no colony seeking policy in this area but unreliable England and France are always unsound and hide the plan to conquer Thailand. The drilling of the Khun Tan Tunnel was started in 1907, which was still in the reign of King Rama V, with a German engineer named Emil Eisenhofer as the first controller and excavating the two sides to meet exactly which requires very accurate calculations. Dug the tunnels on both sides is in the backcountry where the journey must be done by foot or by horse. The construction equipment and luggage Elephants and wagons are required to carry them, sometimes when the mountain is steep, you need to use a winch to go up. The head office is located in Lamphang. Digging method: Start by drilling a small hole in it by manual labor or a drill. Then dynamite, inserted Gap or eruption insertions Then connect a long fuse for the safety the person who ignited the bomb. Some area, use a fire to heat the rock, it easy to erupt or some rock pour water on the hot stone, it will break itself. When they dig into deeper area, it also more difficult. In particular, when they have to take the stone out so the rock that were drilled is about 60,000 cubic meters. Using labor to carry the stones out of the cave, it is an extremely difficult work. The workers who applied for the burden of digging the Khun Tan tunnel, most of them are those who cannot find way to work such as The homeless, drunkards and junkies. So the junkies in that time, they were opium smokers that were not legally prohibited. It turns out that the ones that do the best work are the junkies which are more diligent than other groups. Even though everyone has a skinny body but they work very hard and hope to earn money to smoke opium. And also, there was no fear of the various toxic fumes in the tunnels caused by stone dust because they believed in the power of opium that they could get rid of them all. When they dug deeper, the airs is less and have to pump the fresh air to help But the junkies who is a skin body, used less air to breathe different from the others. Because the Khun Tan Tunnel is in the wilderness that is plentiful with malaria fever. Plenty of laborers were dying from illnesses and there are still many people deaths from accidents since negligence such as connecting the fuse to the fuel gas that they must use the pliers but they used their teeth bite the fuse instead, If the mistake is not fatal, the tooth will fall out of the mouth. After digging the Khun Tan Tunnel for 5 years, a tragedy happened to the Thai people because the King Chulalongkorn the person who gave birth to the Thai Railway, he passed away on 23 October, 1910, but the excavation of the Khun Tan Tunnel still keep continued. Until 8 years later, the tunnel drilling on both sides came through exactly as calculated. After that, it will take another 3 years to make concrete walls and ceilings throughout the tunnel to prevent water leakage from the mountain. While the excavation of the Khun Tan Tunnel has not been completed, Thailand joined the Allies in World War I, declaring war on Germany with deciding to join this war. His Majesty the King Phrabat Somdet Phra Paramenthra Maha Vajiravudh Phra Mongkut Klao Chao Yu Hua, his highness took into account the drilling of the Khun Tan Tunnel and the construction of the Northern Railway which is under the control of all German engineers and they all have the merit of being bestowed with the title of Mr. F. Chanair as Phra Amnuay Ratakij, Mr. Ervil Mueller as a royal performer, Mr. Y. F. Weller, receiving the royal surname, "Vaera Non "when declaring war on Germany, these people were to be taken captive immediately because they were at war. Despite being a good friend of Thai people all along and when he saw that Thailand went to the side of the enemy may be off ended and seek revenge until an unexpected incident happened to the Khun Tan Tunnel. Therefore, on 27 June, 1917, only 25 days before the declaration of war, His Majesty graciously granted His Majesty the King Kromkhun Kamphaeng Phet Akarayothin who studied engineering and engineering from England is currently serving as an Army Inspector General assumed the position of commander of the railway Supervise the construction of all railways. He also has a royal letter to Phraya Sarit Karnbanchong (Saman Panyarachun), a technician in the railway maintenance subdistrict, Nakhon Ratchasima province. The envelope was scheduled to be opened and read on 22 July, a day that was quietly designated as the day of the declaration of war. Phraya Sarit, the elaboration, received the royal and he did not wonder. Unfortunately, it's time to take a vacation so he went up to visit the royal guardian who was a relative who took the position of headmaster of the chamberlain School in Chiang Mai. On 22 July, he opened and read the royal letter, he shocked and hurries to go to Khun Tan Tunnel immediately then he met with Krom Kham Khamphaeng Phet Akarayothin which he had already commanded there. In addition, to the Germans who controlled the excavation of Khun Tan tunnels were arrested and they was stripped of the title and was detained and sent to Bangkok, according to the rules of war. There were still 178 Germans in the Railway Department and the Post Office, all were arrested but it's just following the rules of war, the Germans also received special treatment. They use the Royal Thai Army Hospital at Unakarn Road which is modern like a first rate hotel and there are also doctors and nurses taking care of their health. If any families with children use their own German club on Surawong Road as a detention facility. When the Khun Tan Tunnel was completed in 1918, then it was time to lay the rails but the northern railroad from Lampang has not reached the Khun Tan Tunnel because the landscape is full of ravines and dense forests, it was difficult to lay the rails, especially during the 8 kilometers before reaching Khun Tan, there are 3 deep ravines that cannot be avoided such as Pang Yang Neua, Pang Yang Tai, Pang La, there is only way that they have to build the bridge to cross these ravines which is the widest and deepest at Pang La, plenty of logs were required to build a tower from the bottom of the abyss to support the railroad tracks. When crossing, you have to run slowly and elaborately. It is extremely terrifying for passengers. And used until after World War 2, it was changed to a reinforced concrete tower. Khun Tan Tunnel is now complete. The train was officially opened for the first time on 1st January, 1925 during the reign of King Rama VII. It was the excitement and desire of Thai people who wanted to ride the train through the Khun Tan Tunnel once in their lives. Even during the daytime, the Khun Tan Tunnel is dark. The train had to turn on the lights until it passed through the tunnel. The drilling a rocky mountain into a tunnel so wide that a train could enter and a distance is about a kilometer like this. In the era, it was extremely difficult until almost an improbable miracle but it was possible through human endeavors. As it has been said “Even the river gave way. The mountains must bow.” Especially in the era where technology has advanced as far as today. If human beings will use it creatively Not to be used to destroy, oppress, encroach on each other. The world will become much more beautiful and livable.