• Commuter train from Stockholm City to Södertälje centrum runs about every 15 minutes, then it's a 10-minute walk on pedestrian streets
• Outdoor experiment park with the tightrope bike and camera obscura opens only in set seasons, so the indoor floors carry the rest of the year
• Under-12s need an adult: visitors must be over 12 to come without someone 18 or older

Tom Tits Experiment is Sweden's largest science center, with more than 400 do-it-yourself experiments over four floors and an outdoor experiment park. Kids build a bridge and test whether it holds their weight, pull out a model small intestine to see how long it is, and puzzle through an illusion gallery. No prior knowledge is needed, and many experiments are built at a height small children can reach.