There are a couple of tea estates just beyond the citys northen outskirts on airport road . If you can smile your way past the humourless guard at the gate of Malnicherra; the manager at the general office may be able to provide you with a guard.
Malnicherra Tea Estate (first & Oldest commercial tea garden of Bangladesh), Established in 1854 in Sylhet that is a land of tea gardens.
How you can go there?
You can go by Train, Air or By Bus like: Greenline Paribahan, Hanif Paribahan, Shohah Paribahan etc etc. Also there are many good quality hotels in Sylhet town, Please see: http://www.tourtobangladesh.com/HOTEL-IN-SYLHET.php