A megahertz is one million (or 106) hertz. See hertz, kilohertz (one thousand hertz), gigahertz[?] (109 hertz), terahertz[?] (1012 hertz), and petahertz[?] (1015 hertz).
... Hall Art Gallery[?], Kendal[?] Beatrix Potter Gallery[?], Hawkshead[?] Cumberland Pencil Museum[?], Keswick Dock Museum[?], Barrow-in-Furness[?] Kendal ...