if u want to reach Kanchipuram u can get down at Arakkonam station and catch bus bound for kanchipuram. Travel time will be around one hour.Every 15 to 20 minutes bus to kanchipuram was available. Kanchipuram was famous for silk sarees and temples.
From outside Arakkonam railway station share autos available round the clock to reach bus stand. If u have no luggage means u can also walk it will take just 5 to 10 minutes only to reach bus stand.