Hamartomata, the most common benign tumors of the lung, are rarely symptomatic and usually come to clinical attention as coin-shaped lesions on a routine plain chest roentgenogram. We report a case of a 63-year-old woman presenting with reduced endurance on exercise. The plain chest roentgenogram showed a tumor in the left chest. After clinical work-up, the patient underwent radical tumor resection through a lateral thoracotomy. The resected tumor, with two separate nodules, measured 26 × 25 cm and weighed 3.2 kg. The histopathology work-up showed pulmonary hamartoma.