Galle 119km from Colombo is a major city situated at the trip of the South Western Cost of Sri Lanka. Being a coastal area, It is quite hot and humid but has an abundance of beautiful beaches in every town that you pass while traveling to Colombo to Galle. The Galle Fort was built by the Portuguese, Fortified later by the Dutch and is well preserved till today. In addition to the Portuguese and Dutch remains, You will also find many British mansions left behind.
As for beaches , the Unawatuna Bay probably tops it all and is safe for Snorkeling and Swimming because a reef products it. There you have it a tour of the city of Galle in a nutshell. In case there is a delay in your departure try using the Southern Expressway, a recently built highway that can take you to Galle in half the time.