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　　Yellowstone is a huge park covering over 3, 400 square miles in Wyoming, Montana and Idaho．It can be reached by air to Cody and Jackson, 50 miles from the entrances．There is no train service nearby．Limited bus service is used from some of the towns near it．Once in the area, a car is almost a must．The park has 5 entrances, which are open from May to October．It is a good idea to plan a trip during the good weather, but you may expect big crowds and slow traffic．Parts of the park are open in the winter for snow sports．

　　Be sure to come prepared for different weathers at any time of the year．Take enough of your clothing so you will be prepared for unexpected changes in temperature．Take good walking shoes and thick socks, if you are going to do any hiking．You can also see the park on horseback．

　　If you want to learn about Yellowstone, the National Park Service has many talks, films and tours to help you to understand it．A schedule of these can be found at the tourists' centers．

1．How large is Yellowstone National Park?

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2．What is a must if you are in the area?

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3．Why are parts of the park open in winter?

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4．What do you need to take while going to do any hiking?

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5．Where can you find a schedule of the National Park Service?

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