Well, it's basically quite a good place but if you're not a big fans of culture & history then you can just cut out Polonnaruwa from your itinerary.
Great historical and religious site. Also famous for very interesting wildlife just outside the ancient city, at national parks like Minneriya and Kaudulla.
Plenty elephants & birds.
Spend once day there visiting the ancient ruins with a bike and try to survive the high temperatures!
It is a tourist trap it is very expensive, but if you want to make a model portfolio, then the area is awesome.
There isn't much in Polonnaruwa except for the ancient city. Make sure that before you head to the ancient city site, you have been to the museum and bought your ticket for 25$.
The best way to get around is on the bike, do not pay more than 300 rupees for a bike though!
not meant for shopping but can pick up bargains in the not too tidy town.be very care ful of roads if you are driving as jaywalkers are aplenty.
dont miss nearby minneriya and giritale tanks on way from colombo and the genuine safari parks of kaudulla and minneriya on way.jeeps with guides on hire at entrance.not for budjet backpackers and hippies!
The cultural aspects are why you should visit this region as part of the cultural triangle it is a must see.