It is true that you will swim up to 1 km on the Tu Lan Cave Encounter 2 days in 4 river caves. The shortest part is 70 m and the longest part is 250 m and all customers are required to wear a life-jacket while on tour due to safety purpose, regardless of swimming abilities. If you cannot swim at all but insist in doing the Tu Lan tour, your tour guide and safety assistant can assist you in the swim portions.