From skateboarding without a helmet to attempting any exercise at all without stretching, some activities that seemed totally safe in childhood can be downright dangerous in adulthood.

The hashtag #DidAsAChildButDangerousNow trended on Twitter on Friday morning as social media users reminisced about the activities that they used to love, but would be far too dangerous for an adult to try.

Here are 10 of the best examples, with one bonus, of the hashtag in use, which might make you nostalgic for your indestructible childhood years.

1. This person jumped off every surface in sight.

2. The heat burns from metal slides are best left forgotten.

3. If only this activity could last beyond childhood.

4. This person experimented with the urban myth that cola and popping candy makes your stomach explode.

5. Don't try this activity at home.

6. Hopefully no light bulbs were broken during these fights.

7. Climbing trees is the best way to spend childhood.

8. Children really can be fearless.

9. This sad reality in adulthood.

10. Lastly, this should never be tried, whether in adulthood or childhood!

Bonus: skateboarding!