Yongding tulou, see the answer to the question

1. The main features of Yongding Tulou are firm, easy to defend but difficult to attack, warm in winter and cool in summer, and large in area.

2. A masterpiece refers to an outstanding work. The reason why Yongding Tulou is wonderful is mainly because it is huge, but it doesn't need a brick or a tile.

3. The second paragraph of the article mainly uses figures to explain and analogy.

Take the architecture of Shenyuan in Jingtou Village, Kuzhu Township, Yongding County as an example. The building has three circles, with a diameter of 80 meters and a circumference of 250 meters. The outer ring has four floors and 260 houses; There are 60 houses on the second floor of the middle circle; There are eight houses on the first floor of the inner ring. * * * There are 328 houses, 80 families and 500 people poisoned.

For example; Like a huge mushroom that naturally grows from the ground, it is like a black flying saucer falling from the sky, with a round roof floating in the smoke.