We present a new design of a low-temperature ultrahigh-vacuum (UHV) scanning tunneling microscope setup with a combination of a solenoid and a split-pair magnet. The scanning tunneling microscope can be operated at temperatures down to 8 K and in a rotatable magnetic field of up to 1 T. Magnetic fields of up to 7 T perpendicular and 2 T parallel to the sample surface can be applied. The UHV part of the system allows in situ preparation and low energy electron diffraction/Auger analysis of samples. First topographic and spectroscopic measurements on p-InAs(110) are presented.