Question

what are the worth visiting places in siam , especially 4 kids( in summers) ?

Location

City: Bangkok

Province: Krung Thep

Country: Thailand

Answers

Yes, there are many places you can visit there. Siam ocean world at Siam paragon is a nice aquarium. also, the recently opened Madam Tussauds Bangkok is at Siam Discovery Center. Malls in Siam area itself, especially Siam Paragon, is also kids friendly ;)
I would recommend Siam Ocaean World at Siam Paragon and Madame Tussauds at Siam Discovery as well.
Hello, the places mentioned by the other folks are good fun places in the Bangkok downtown region. There is also an observatory center in the same region. But, how old are the children? They have bowling and there is the river market and the Chack-a-chak open market on the weekends also. Just "easy" I am sure is what your looking for isn't it? You might ask the hotel people where you will I gather will be staying what they can recommend also. The Thai people are great hosts and very helpful. Be "nice" get back "nice". I guess it also depends on how temperamental your kids are. Have a great time. ":^ )
Yes so many place is nice for you. Siam paragon is nice and you can visit Jim Tomsan is very famous about thai's silk too.
The previuos recommendations were for Bangkok only, and if you don't find Chak-a-chak try Chatuchak week endmarket (take BTS Skytrain Sukumvit line to Morchit terminal station).
However I guess that with 4 kids you won't spend all of your precious holidays in Bangkok city.
A nice beach site with some activities could be what the kids would like, I reckon. With the upcoming summer monsoon all places on and off the east coast of the peninsula will be better in terms of weather than the west coast. As this will be the so-called "green season" you will be able to negotiate good prices.
ancient city in samut prakan, khao jai national park, 4 theme parks in bkk., and the whole isaan - north eastern thailand
Instead of bring kids to enjoy beaches only, we should bring to them to some museums to add more general knowledges for them also people life ways such as floating markets, more details in this link
phuket
Outside of downtown - Try - The zoo (it's great), the Teak palace, a tour boat trip on the ChaoPraya, , The theme parks (I think one is called Dreamworld) - Elephant parks and Floating markets? (like on the way to Nakohn Pathom) - Ancient city, etc.
Highly recommended is the Siam Ocen World.
This is located inside the Siam Paragon Mall.

If you have spare time, and want to relax, visit Benjasiri Park, in front of Phrom Pong BTS STation. This is a usual place for expat families on weekends. They have a playground, a lake in the middle of the park, and a small swimming pool also.

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