  We report a direct measurement of the $7s\ ^2S_{1/2}\rightarrow$ $7p\
^2P_{3/2}$ electric dipole transition frequency in $^{226}$Ra$^{+}$. With a
single laser-cooled radium ion we determine the transition frequency to be
785722.11(3) GHz by directly driving the transition with frequency-doubled
light and measuring the frequency of the undoubled light with an iodine
reference. This measurement addresses a discrepancy of five combined standard
deviations between previously reported values.
