Varanasi is a Spiritual Capital of India.
First Place : Old Kashi Vishwanath Temple
We visited Old Kashi Vishwanath Temple at early dawn.
Second Place : We Visited Kal Bhairav Mandir
Third Place : Sarnath
There are so many temples are in Sarnath. if u visit each and every temple it may take your 75% of the day. All temples are made by different countries like Thailand, Sri Lanka, Japan, Korea, Tibet, Nepal, China. Famous one is made by Sri Lanka temple u can visit inside the temple but there is a small place which opens at 1.30pm so u have to make a plan accordingly.
Fourth Place : Deena Chaat bhandar. This place serves number of fast foods try to have Tamatar Chaat, Papadi Chaat, Kachori Chole, Panipuri if u r bhelpuri fan just walk on little upside of deena chaat bhandar in 100 meter u will see Kakka Ji Bhelpuri they serves good bhelpuri.
Fifth Place : Visit Sankat Mochan Hanuman Temple, Durga Temple, Manas Temple. (all places are nearby it will take max 2hr to complete
Sixth Place : BHU, New kashi Vishwanath Temple. Visit it and then have some Lassi and Banarasi Paan. ;) ( Almost 500 meter from BHU gate)
Seventh Place - Go to Assi ghat. and take a ship or walk through all ghats timing should be around 5pm. go to Dashashwamedh ghat (which is just nearer to old kashi Vishwanath temple). Have some fun in river. (If u r willing to spend one more day then u can able to see some Naga/Aghori Sadhus during Ghat walk.)
Eight Place - Most Beautiful Part in Varanasi is attending Ganga Aarti it starts at the end of evening. no particular time.