Sounds like a bag someone put together for grouped digging. I often group Tmaps by location to dig up multiple without having to recall or gate around.
I saw one of your (or someone else's) characters offering this bundle of 16 maps at Occlo bank the other day. I'd just returned from holidays and was feeling unwell, so didn't look into it. Here's T-Map spot #11 https://uo.stratics.com/thb/info/maparchive/archivemap.shtml?mapsection=B
Hah I miss the days of bank-selling! It is one of my first memories of starting on Oceania back in 2000, when people would be selling anything and everything, including horses for 250g! Brit bank was the hub of the server. My experience is limited on this server(especially since I went on holidays for 9 days since starting) but the general price I have seen on Occlo vendors is 1k per level 1 T-map. From memory, you get 1k gold from level 1 t-map plus a bunch of other (generally crap) stuff but they are really swift to get through. @Keza has posted some great videos on Youtube about caning through those maps. What I don't understand, is why you don't do them yourself? Cartography skill needed = 0 (can a map decoded by another be dug up by another - that's where my hesitancy would be at) and 0 LP needed for level 1 maps - 50 magery opens them, as 100 magery opens level 2 T-map chests. Use an axe on the empty chest, and you can cane through those 11 chests.
You might want to check with @The Ferret of Baja if this is his. I know he does maps like that, and perhaps he accidentally dropped it and didn't realize!
*beams* My thanks for the esteem! I am honored deeply by your statement! *tips hat* As far as those particular spots go, I don't really think they stand out too much... Lemme see what I've gotten from them in the past.. (consulting tally) 11 -- Nothing in particular stands out.. I had to evade a red highwayman there a few months ago, but I've not really seen any more goods from that spot than any others. 20 -- Right in the middle of Southern Chaos Valley.. It's next to a brigand camp, so there are chances of adding to your net gain with the chests and guardians there. 25 -- Rather close to the Buc's den teleport spot and east of Covetous, so could be a high-traffic cutthroat roaming area. Come to think of it, on closer analysis - those could all be considered somewhat higher-risk from the presence of the more murder-inclined. I know my least-favorite haunts are the areas near Shame (34, 35, and 38) and Destard (123-125) due to the presence of cutthroats. As Sky has mentioned, and like Keza - I do "batches" of up to five maps in one spot at a time after having sorted bulk-purchases by location. But I would not keep them in bags; they are stored in my villa's vault, so these would not have been mine.