About a week ago I was on a 737 sitting on the left side of the aircraft. We were flying north, gear down, probably about 2,000 feet (not sure, it was dark) and getting ready to land on runway 34L. There is an interstate that runs east/west just south of the airport and I could clearly see it up ahead of us so we had to be only a couple of miles (if that) from the runway. All of a sudden we stopped decending, the engines came up and we started a pretty steep bank to the right. As we turned I could see the runway that we had been linded up with. We continued to make a full 360 degree turn at which point we leveled off, started descending again, and landed about 3-4 minutes later.
I have never expericned such a thing before and was just wondering if anyone knows why a manuever like this would have occurred. Several other passengers seemed to be puzzled/uneasy when it happened. Maybe another aircraft on the runway that we were headed for?