I'd like to insert a picture (figure) into a document which is using a two-column layout. However, I want it to take one whole page and not be centered on one of the columns. Currently if I add a [p] modifier to the figure, the whole image lands on the last page, instead in the middle of the document.
How can I force one page to switch back to a single-column layout and insert a single big picture there?
\usepackage{multicol} in your preamble.
Then
\begin{document}
\begin{multicols}{2}
blah blah blah text
\end{multicols}
\begin{figure}[H]
\includegraphics[width=1\textwidth]{arc}
\end{figure}
\begin{multicols}{2}
blah blah blah text
\end{multicols}
\end{document}
This is ugly, and dirty. and you will need to fiddle with where you figure is in order to get the text balanced, but it is exactly what you asked for.