My favourite wonders of Vietnam is Ha Long Bay.It is in Quang Ninh Provice .Ha Long Bay is very beautiful.Around Ha Long Bay are Bat Tu Long Bay,Lan Ha Bay,Cat Ba Island,Tuan Chau Island and Ha Long city.Although it covers an area of 1533 square kilometers but Ha Long Bay own about 1600 limestone islands. Limestone islands have different shape.Ha Long Bay has both a good atmosphere and a beautiful place,so many tourists come here.There you can take photos,take a boat on the river to see all the landscape,enjoy great seafood,join exciting activities.Ha Long Bay is great,isn't it? I think you should go there at least once.

             Chúc học tốt ạ ^ ^

Phong Nha cave is acknowledged one of the cultural heritage sites of the world with an unsurpassed wonder of nature.

It was formed by tectonic happening in the heart of Ke Bang limestone mountains hundreds of millions of years ago. - It is 7,729 metres long and contains 14 grottoes, as well as a 13,969 metre underground river - Its cave system features underground passageways and river caves filled with stalactites and stalagmites. - wonderful caverns in Phong Nha cave as the “Lion”, the “Fairy Caves”, the “Royal Court”, and the “Buddha”

It is truly unforgettable thanks to its long history and astounding natural beauty.