Greetings for the day.
I wanted to know that can a Muslim travel to Vatican city?
Yes, here there aren't problems for anyone, if you can show your face.
There are two parts of the Vatican City that can be visited by the general public - St Peter's basilica and the Vatican Museum complex which is about 15 minutes walk away around the Vatican City walls. Although it is a separate country, there are no entry requirements into the public parts of the Vatican so you just walk straight into the piazza in front of St Peter's. I am not aware of any restrictions and there certainly isn't anyone who will stop you. There is obviously a security presence in the area and anyone who causes trouble, regardless of religious affiliation, would be dealt with.
If you wish to go inside either St Peter's or the museums, you have to pass through security scanners. Unless you go very early in the morning (St Peter's opens at 7am usually) there is likely to be a queue so you may have to wait 30 minutes or so at busy times. Visiting in the morning befoe the crowds arrive is a lovely way to experience the basilica.
You can also attend religious services at St Peter's although it is requested that non-Catholics do not participate in Communion.
If you wish to visit the museums (which includes the Sistine Chapel), it is strongly advised to book tickets in advance as the ticket queue can be horrendous. Book on the Vatican website as otherwise you will pay more for the same thing. The system won't let me post the link in reply to a question but search google for 'musei vaticani' and it should be the first item.
If you are visiting in the summer months, the Vatican opens in the evening on Fridays from 7-11pm. If this fits your itinerary, book entry for 7 or 7.30pm and you will see the museums and the Chapel with fewer people. Not everything is open but the most popular areas are and there are fewer people aroound so it is a more enjoyable experience.
I hope this helps but just ask (or check out the Rome forum) for more information.
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