what is "welcome to iran" in iranian language???

Which language?

http://en.wikipedia.org/wiki/Languages_of_Iran

Once you decide, try this:
http://babelfish.altavista.com/

english to persian language (farsi)

http://www.google.com/search?q=english+farsi+translate&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&sourceid=ie7&rlz=1I7SUNA

To find out how to say "Welcome to Iran" in Persian, you can follow these steps:

1. Start by searching for "translate" or "translation" using your preferred search engine.
2. Open a reliable translation website or online dictionary that offers translation services for English to Persian, such as Google Translate or a trusted language-learning platform like Duolingo.
3. Once you are on the translation page, you will often find two fields or boxes where you can enter the text. One will typically be for the source language (English, in this case) and the other for the target language (Persian).
4. In the source language box, type "Welcome to Iran" and make sure it is correctly spelled.
5. In the target language box, select Persian or type "Persian" or "Farsi."
6. Click on the "Translate" button next to the text fields or in the interface. This will process your request and provide the translation.

Keep in mind that while online translators like Google Translate can be helpful, they might not be 100% accurate. It's always recommended to double-check translations with native speakers or language experts for more precise and reliable results.

In Persian, "Welcome to Iran" translates to "خوش آمدید به ایران" (pronounced "khosh amadid be Iran").