This is a lovely piece about the sufi dargahs in India and Pakistan originally from the Huffington Post. If you follow my posts on Facebook about Sufi Urs and Event Dates, then you will see pictures of many of the dargahs there. She does go into some of the history of Sufism in the subcontinent and talks some about Nizamuddin and Amir Khusro. There is a discussion at the end of the post which gets a little rough at times, but people do mis-understand or have their own agendas so it is hard to avoid that kind of thing these days.
The article was originally posted in the Huffington Post and has some very nice pictures in addition to the one I have posted here.