The first ten prime numbers are:
\[
2, 3, 5, 7, 11, 13, 17, 19, 23, 29
\]
The median is the middle value when numbers are ordered. With 10 numbers, the median is the average of the 5th and 6th numbers:
\[
\text{Median} = \frac{11 + 13}{2} = 12
\]
Therefore, the answer is 12.