\documentclass{article}
\usepackage{graphicx}
\usepackage{lscape}

\begin{document}
\begin{landscape}
  \begin{figure}[htbp]
  \includegraphics[width=8in]{box.pdf}
  \caption{A landscape figure created using the \texttt{landscape} environment}
  \end{figure}
\end{landscape}
\end{document}