OK, so it is summertime and we are probably thinking of holidays. For some this means getting to the airport and jetting of somewhere. For others it means road trips. I fall into the later category and the thing I love about road trips is planning the route. Why? Well it means looking at maps. This used to be a paper-based exercise but increasingly means looking at online mapping, many of which feature built in route planners.
The road trip
- From EDINA HQ in Edinburgh to Dover
- From Dunkirque to Aime
- Google maps A1 – 469 miles in 7hr 48 min / M6 – 499 miles in 7hr 50min
- Bing Maps A68-A1 – 451 miles in 8hr 25min
- AA A702-M6 – 491 miles in 8hrs 25mins
- ViaMichelin A1 – 467 miles in 8hr 27mins / A702-M6 – 481 miles in 8hrs 58min
So it looks like google is the only one to predict sub-8hr journeys. The A1 route would see me averaging 60.13mph while the M6 route would mean averaging 63.73mph. Is this realistic? I reckon i can comfortably do 3hr stints and we have 2 drivers so lets say we have 2 stops for driver changes and “comfort breaks”. This will add 10 mins per stop so that is 20 mins making the revised times 8hrs 08min and 8rhs 10mins.
The M6 route is simpler so lets look at why we have 18 miles of variation in distance. part of the variation seems to be from the route choice out of Edinburgh. There is no obvious route differences that explain the extra 10 miles or so, and this could also explain some of the differences in travel times. In addition, Bing seems to route you off the M25 onto the A2 rather than the M20.
The route that i would take to get out of the city is different to the routing results. My route is complicated, but misses out traffic lights, right turns and bottle-necks. I reckon it saves 10 minutes getting out of the city during rush hour. Local knowledge does count for something. Where these websites really excel is when you don’t have “local” knowledge. So lets look at driving on the continent where we can throw in “avoiding road tolls” to make things more interesting.
Route – Reims* to Aime in the Savoie avoiding tolls**
- Google – 589km in 8hr 38min
- Bing – 593km in 9hr 1min
- AA – no way to specify avoid tolls. (edit – you can, but the interface is so buggy that you can loose the “options” menu.)
- ViaMichelin – 628km in 10hr 2mins
Bing and Google seem to use the same route. The difference in distance is negligible and the time difference (23mins) will be as a result of different average speeds used for certain sections. Via Michelin seems to use a strange route that looped into Switzerland and just looked wrong even on an overview map. The AA had no option to avoid toll roads.
* Note – avoiding tolls adds 3 hrs to this journey. If you want to see the cost of tolls then the AA has a great page detailing the pricings for each road in Europe.
**Note- starting this route in Reims as the it is easier to stick to the motorways in Northern France.
Both Bing and Google are easy to use. The mapping control is familiar and slick and it easy to see the various routes (fastest, shortest, avoid tolls). Google has a mouse over which highlights the route instructions on the map. However, this route is heading North to south and the arrows appear for a “north at the top” scenario. This means that a left turn appears to point west rather than east. Basic tip – always orientate the map in the direction of travel, makes left/right much easier to get right.
The AA and Michelin are less polished but they do excel in the detail they provide in the print out notes. They even calculate the cost of the trip. However, both the AA and ViaMichelin seem to be less reliable for directions on the continent. Not sure why.
So what will I use? Will probably use Bing and Google as a start point and then tweak the route using paper maps. Well, it is nice to have an excuse to buy a new map after all.
GIS – well it is a GIS blog…..
All the routers here are using routing algorithms that are available in some GIS packages. What they do is to store the road network as lines. Each line is cut into segments at junctions. Each segment will have attributes which describe the speed limit and anything else that might be useful such as width restrictions, one-way sections and tolls. In addition there will be features such as bridges which will have height limits. So when we put in directions they are queried against a place name gazetteer such as Unlock. Once you have a start and end point you feed these into the router and it scans the network to return possible routes. With the speed limits it can estimate time and offer these back to the user. Quite simple, but quite complex when you apply it to a huge network such as mainland Europe.
The web-based tools allow live traffic information to be fed into them meaning drivers could adjust their route to avoid incidents on the road. Having a live data connection while out on the road is becoming the norm.
EDINA Digimap subscribers can access Ordnance Survey Mastermap Integrated Transport Data (ITN) through the Digimap Data Download service and experiment with routing.