Can you post on Instagram without Wi-Fi or connection?

I'm going to vermont in a few days and I'm being told there's absolutely no connection there, which doesn't make sense to me unless I'm in the mountains. I have an iphone so I get good Wi-Fi just about anywhere. Is there really 0 connection in somewhere like vermont? I need to use my instagram for only a few minutes to post something. Is there a way I can post something without perfect connection?

There are TWO Ways to connect to the Internet with your iPhone. Through the DATA connection that uses the CELL phone system or through a Wi-Fi HOTSPOT.
and yes you have to be connected to the Internet to use Instagram.

If you have cellular Internet on your phone, you should have a connection if you are within a small number of kilometres of a cell mast, subject to terrain and your specific location.

For Wi-Fi, you will normally have to be within 100 metres of so of a Wi-Fi network. You will also need permission to use that network otherwise you are committing theft. If the network is encrypted, then you will need the pass phrase to get onto the network.

In rural areas, Wi-Fi networks might be few and far between. As for cellular networks, you should contact your cell company for coverage maps of your planned locations.

You will need the Internet to access any website, including Instagram.