Valmiki Ramayana Sundara Kanda Sarga 8 Shloka 4

तपः spiritual efforts, समाधानपराक्रमार्जितम् designed through concentration and prowess, मनः समाधानविचारचारिणम् which can reach the places desired by the thought of its master, अनेकसंस्थानविशेषनिर्मितम् built with many special seats, ततस्ततः at all places, तुल्यविशेषदर्शनम् of equally good appearance

(The Pushpaka) was designed by dint of divine efforts and prowess (of Kubera). It could touch any place its master commanded with a cool mind. It had many beautiful places of rest.