My book is mostly medieval era fantasy, but there is one notable sci-fi-ish element. There are obelisks that surround the main city, Talora, called S.E.O.s (Shield Energy Outposts).

What they do is they are the energy posts for a shield that stretches like a dome over the entire city. The shield helps control weather, but it does not keep things out.

Do you think this is an okay element to put in a medieval fantasy book?

It depends on how they are powered. If you have huge generators giving off 1000000 watts a hour, then that wouldn't be fantasy. But if you used, say, a council of wizards frozen in time, bound to power this field so that the city isn't damaged by bad weather, then that would be fantasy.

Does that help?

I agree.

First, a confession: I only came here to figure out what SEO meant since it didn't appear to mean search engine optimization.

In speculative genres, anything flies as long as it is realistic to your world. Now, your world can be anything. A good way to gives things a more realistic feel is to have rules regarding it. An example is magic systems. A do-everything magic system will create confusion, plot holes, and become a deus ex machina. However, create rules and limitations, and you have a plot device.

To add to what Vace is saying, it is possible to have advanced tech in fantasy. It's called science fantasy, and is now a very popular cross genre.

*disagrees*

Like Kathrine said, as long as it makes sense for your world, then it's fine.

Yeah, if the way your world is set up allows it, and makes it work, it would fit.

Okay, obviously I agree that if it fits your world, then it works.

But if you're aiming for medieval fantasy, you want to do certain things, right? *goes and looks up 'medieval fantasy*

"Medieval fantasy is a subgenre of fantasy that encompasses medieval era high fantasy"

Maybe the above definition isn't the most popular definition (I know it's pretty much impossible to completely pin down a genre), but that is what I'm thinking of it as...
So it seems like if you're allowing cobhacal magic (or whatever you call it), you probably want to use that.
If you're allowing high-tech stuff even though you're aiming for a medieval feel (which doesn't make sense to me, seems counter-intuitive), then you could have a huge generator or whatever.

So what it comes down to is your definition of medieval fantasy and what fits with that.

Well, you can still keep the feel of medieval fantasy, even with it being a more science-fictiony type thing. After all, the people around don't have to know anything about how it works. What's to distinguish it from magic?

Umm...if it is a complex invention (which a huge generator type thing seems to be, in my opinion), then I think that they would have to know about electricity or how it works, and then why wouldn't they be using it in other ways too? Why would it still seem like the medieval era when they have such advanced technology?

I do agree in part though, they had batteries a really long time ago, you could probably put a lot of thought into it and come up with something that could do that that isn't "magic" and also isn't sci-fi-y either...I guess that's all up to you.

Only if these people made it. Ancient things no one understands anymore that still operate are pretty common, I think, in fantasy.

Yeah, that would be an interesting way to do it.

Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic."

One of the things that distinguishes science fiction from fantasy, and the sub-genres of each from one another, is "feel," a nebulous concept including obedience to genre conventions and jargon, among other things. Whether a particular element "works" or not in a given story often depends on how it's described; a humanoid automaton could fit in a SF story if described as a "robot", or in a high-fantasy story if described as a "golem", but would be unsettling in both if the terms were switched, for example.

I think that illustrates it pretty well, though I've not encountered the term "golem" very much.

*loves golems*

Thanks so much, everyone, for your input. I have taken it all into consideration!