It's a great place.

Here is more information about it. I like the blue tiles.
http://www.bigloveturkey.com/pages/blue-mosque-turkey.asp

I consider myself lucky. Because I work near Sultanahmet Mosque and I walk through the park admiring both Hagia Sophia and Sultanahmet Mosques every day! A Mosque is considered the house of the God (Allah) so of course it is free and everyone can come in. As a muslim I have visited Vatican also and there were similar limitations on the clothes. ...

sultanahmet or blue mosque is great building. its very exciting..I would back because i like there...sultanahmet and hagia sofia have great build and amazing history.....

This place has the one of the best architectural and interior design I've ever seen. i surely recommend it if you've visiting turkey, but remember to wear thick socks if you're visiting in the winter!

You may have seen pictures of the place online, but i no way will they do any justice at all. Until you are standing there beneth the great dome, head covered in a scarf as muslim women do, you can not possibly understand the meaning and beauty of this place. It is incredible, truly increible. It almost made me cry, the beauty and what it stood for.

This is exactly what I imagined it to be! Beautiful in the inside, very impressive outside! A must-see when in Istanbul! Dont forget to wear long trousers/skirts!

Skip this and see Hagia Sophia instead. The Blue Mosque was a muslim attempt to rival the christian Hagia Sophia. The attempt failed.

An excellent beautiful Mosque thats still in use so try to avoid going on Friday cause you wont be able to get in while they are in Prayer. Worth the time to see it, plus its FREE!!!!

I JUST WANT TO SAY THAT THE WHOLE TURKEY IS GREAT, NOT JUST ISTANBUL OR BLUE MOSQUE. MAYBE WE SHOULD HEAR MORE ABOUT IT BY A TURKISH MAN, OR BOY/GIRL... I WOULD RECOMEND IT TO ALL, IT IS WORTH YOUR MONEY