Can I use this AT&T iPhone on the Verizon network?

I've recently obtained a AT&T iPhone for free that's in very good condition… Only I'm on the Verizon network.AT&T has horrible coverage in my area, while Verizon has towers all over here. Can I use this phone with my current network? If not, any suggestions?

No.
att is gsm and verizon is cdma.
what iphone is it?

Iphone 4s aqnd newer are dual network. It depends on the model of iphone you have