So lately I've been making daily 5 minute bike rides to and from the local pool but due to some clash in hours I have to go to another pool which is a bit further and even though I should be getting my license this year I don't plan on driving much in the next few years. I have a friend who also swims and think he has some Bridgestone road bike and it really was a lot more efficient and a much better ride.

I came across this forum and I saw lots of other bikes like singlespeeds or some cyclocross or whatever.

What type of bike should I get???