In this paper, we study and investigate an interesting Caputo fractional derivative and Riemann–Liouville integral boundary value problem (BVP): c , where , , , , and c is the Caputo fractional derivatives, , where E is the Banach space. The space E is chosen as an arbitrary Banach space; it can also be (with the absolute value) or with the supremum-norm. RL is the Riemann–Liouville fractional integral of order , , and . Via the fixed point theorems of Krasnoselskii and Darbo, the authors study the existence of solutions to this problem. An example is included to illustrate the applicability of their results.