There are many exchangers right now which are best in the market for providing exactly right volume for you to sell your BTC. Its good that you are holding the BTC since 2014 and it is even interesting that you were holding it since 2014 and you did not sell them at ATH of 2017. I liked your attitude but I would say you should hold even further because we will soon see prices of bitcoin going above 20K USD for sure. If anyway you want to sell then I would say only Binance can help you for selling your huge pile of BTC bag.