Sunday, 9 August 2015

Cycle Trail Maps

Back here I did write about the maps available from the NZ Cycle Trails website which, theoretically, could be added to my maps. I'm kind of split over that. The raw GPS trace can contain inaccuracies, so either I can post the raw traces and mark them as "approximate", or wait until the routes become visible on some other map then work from both sources.

For the interest of the maps I draw I think it will be a case of waiting until more information is available about the reuse of each rail route, so the maps won't necessarily show the full cycle trails, but will focus on rail trails more. Perhaps the easiest way is to wait for Linz to update their layers and then bring those in, which I expect will be the quickest and simplest way of getting the data into maps. However, some questions over the use of rail routes may linger where there is a possibility of deviations from these routes.

UPDATE: Well I thought the easiest way to check would be to download the latest LINZ tracks layer, this is the layer that contains everything they define as a track, including cycle, foot and vehicle tracks. Although there are some that have been added, I didn't see a whole lot of new ones or all of the nzcycletrail ones. Which is a pity, but we hope that they will update. Here are some examples:

I know about the Roxburgh Gorge trail because of it being marked on Google Earth, along with Panoramio photos. And according to both of those the trail is on the west bank of the river, so it is not the existing foot track we can see on the east bank down to Doctors Point. Now, I have shown the data from the new table as green lines - and underneath that you can see dashed lines, which means they were already in the map, and the "foot" symbol shown in a number of places above is also part of the existing map symbology. So surprisingly perhaps, considering it's more than two years since some of those Panoramio photos were taken, no trail.

This is more promising - down between Minzion and Millers Flat - with no existing track marked under the green, that is a new section - and it turns out that is classified as a foot track and it does correspond with the GPS trace from Unfortunately that's as good as it gets. 

So here for example is Big Hill Tunnel - that's been open for some time I believe, well in advance of the trail (unless I confused it with one of the other tunnels like Manuka). But no marking.

OK I understand Linz are busy people and this is a free service - and if they are using traditional techniques from aerial photography, it also depends on how often that photography gets updated.