This is the longest train journey in the world, running from Portugal in Europe to Singapore in Asia. It takes 21 days to complete the journey along the 18,755 km route, which crosses 14 countries.
The train journey from Portugal to Singapore is an epic journey that passes through 14 countries:
Portugal: The trip begins in Lagos, Portugal 
Spain: The train passes through the stunning landscape of Spain. 
France: Enjoy the charming French countryside 
Germany: Discover the rich history and culture of Germany -
Poland: Explore Poland’s historical landmarks,
Belarus: Pass through the green landscape of Belarus and stop in its capital, Minsk.-
Russia: I bear witness to Russia’s greatness in... -
Mongolia: Enjoy the beauty of Mongolia's scenic landscape and experience its unique culture.-
China: Discover the ancient civilization of China 
Vietnam: Enjoy the picturesque landscapes of Vietnam and taste delicious cuisine.
Laos: The railway was completed, making the journey possible.
Thailand: Discover the magnificent temples and rich culture of Thailand 
Malaysia: Enjoy the diversity of cultures and landscapes in Malaysia. -
Singapore: End your trip in Singapore, a vibrant city with modern tourist attractions.Source: websites