A large number of rooms (obviously hotels) are needed to accommodate these visitors. Government as well as private players are doing their part for fulfilling the demand.
Just have a look at some of the renowned hotels in the National Capital Region..
The Hotel s are:

* City Park,
* Vasant Continental
* Crowne Plaza
* Galaxy
* Grand
* Hyatt Regency,
* Le Meridien,
* The Metropolitan
* Taj Palace
* Taj Mahal
* Oberoi,
* Shangrila
* Sheraton
* Siddharth
and many more etc...