I traveled for 2 year straight and many times didn’t have a gym.
Abmat sit-ups with a rolled up towel
push-ups
squats
burpees
sprints
jumping jacks
stair climbs
step ups/jumps on stairs
jump rope (easy to store)
hold your suit case or bag and do SDHP or Kbell swings
hold your suit case overhead while squating
handstand presses
Get creative and get it done!