I usually don’t think much about toll roads when I’m on vacation. I stop, pay the toll and go on my way. OK, maybe I complain a little about the cost, but that’s about it.

But this year when the Muse and I were traveling in Portugal we became somewhat obsessed with toll roads. Well, not with the roads themselves but with trying to pay the tolls. Since then I’ve spent some time on the internet and I’ve found we are not alone in being utterly flummoxed by the new toll roads in Portugal, where the only convenient way to pay the toll is by having a transponder on your car.

We had rented a car without a transponder because we have gotten in the habit of turning down all the extras they try to add on to increase the rental fee. Admittedly, we should have paid more attention, particularly when the rental agent, who really was trying to help us out, showed us a photo of the toll roads he was talking about.

At the time I wondered what he was doing; did he think we had never seen a toll road? But he was right – we had never seen toll roads like these, and without the photo we might have been even more confused than we were, which was pretty darn confused.

The toll roads, as far as I know, are unmarked, except for a little sign that I thought meant Wi-Fi was available on the road. But the tolls do have a big steel framework with all kinds of antennas and stuff on them over the road, which is what the rental car guy showed us in the photo. All that stuff is to pick up your transponder signal and take a photo of your license plate.

So when you drive under one of these things you know that you are now on a toll road, but there is no way to actually pay the toll while you are on the road, and what we found was there was no way to get off if you don’t want to pay the toll.

If you are driving in a transponderless car like we were, your only payment option is to go stand in line at a post office and then, when it is finally your turn, you give your license plate number to the clerk, who looks it up on his computer and then you can pay your toll.

Except, as we learned, it is more complicated because the tolls apparently don’t show up on the post office computer for two days and, in true bureaucratic form, you have five days to pay the toll – which you can’t pay for the first two of the five days.   After five days they start adding fines for not paying the toll.

When we were leaving the country we found ourselves in a situation where we couldn’t pay the tolls because we turned our car (which other than not having a transponder was a wonderful car) in on Thursday and flew out on Friday. So when we left our tolls had not showed up on the post office computer.

The first time we stopped into a post office to pay the tolls it was kind of interesting to find out how the system worked, but that was before we found out about the 48 hour rule, so we were mainly just confused. I can’t imagine what people who don’t speak Portuguese do, since the folks in the post offices we visited were helpful but didn’t speak English very well.

Later, at another post office, we found out that foreigners could buy a one-day or three-day pass for the toll roads, but then we discovered we couldn’t buy a pass because it is only available to people driving cars with foreign license plates, and the license plate on our rental car was Portuguese. So our only option was the post office.

On the internet, the people who seem most upset about the whole system are people on vacation from Germany or Great Britain, who don’t have transponders, and, if they knew about the system, couldn’t find anywhere to buy a pass and didn’t want to hang around the border for two days to pay their tolls before they left the country.

We are still expecting to get a bill from the rental car company for the tolls we couldn’t pay, plus a fine that no doubt will be more than the transponder would have cost.

Since we’ve been back I’ve tried to explain the system to a few people who thought I had lost my mind, but then I was talking to someone from the North Carolina Department of Transportation who said the state was considering the same type of toll roads here.

I can understand the attraction because it looks so good on paper: You collect the tolls without having to pay people to sit in toll booths or even incur the cost of putting equipment out on the road to accept payment.

On paper it looks great, but on the road it is a mess.

Some of comments online are from people who vow they will not return to Portugal until the system is changed. In North Carolina, I don’t think people would be so nice, except that there is no one around to yell at and, of course, in North Carolina people couldn’t pay at the post office because that is federal and I don’t think the federal government is going to collect money for North Carolina without tacking on a hefty collection fee.

It is such an infuriating system I have no doubt that it will be coming to a road near you soon.