My Mil managed to 'escape' from a secure day care centre. No one could get in unless staff let them in, but at that time, visitors were given the code to get out. We think Mil either managed to get out through a side gate in the garden (which had been left unlocked by workmen) or she had done what so many are able to do - managed to convince another visitor who was leaving that she was a visitor too, and simply walked out with them.
She made her way to the premises of a disabled childrens day centre, a journey that we think took her the best part of an hour, told them that she had been 'at the church with a choir' from where she lived and that the bus had gone without her by mistake. She asked them to phone her a taxi, and gave them the address of the house she used to live in, about 12 miles away. Thankfully, staff at the childrens day centre realised something wasn't quite right, and instead, phoned the police. Equally thankfully, we had - after she had managed to 'escape' from our house several times - registered her as a vulnerable adult with the local police, and they eventually contacted us. We went and collected her, and headed back to her day care, thinking that they must be frantic with worry - only to find that they hadn't even noticed her missing. She had been gone, we think, for nearly 3 hours in total.
The day care held up their hands, apologised and took full responsibility. They changed the door codes (just in case) and visitors were no longer given them. Just over a week or so later, a member of staff looked out the lounge window, and spotted Mil pegging it up the road again. And again, they had no idea how she had got out.
Having witnessed first hand ourselves how determined, and clever and devious she could be in her escape attempts, it was hard to blame the day care too much, and at least they fully admitted responsibility, apologised and tried to make sure it didn't happen again. We thought we had thwarted all her tricks to get out of our house, yet at 2am one morning, she came downstairs, stood on a chair to reach the key to the patio doors (which was high up and hidden from direct sight), negociated a gate (with 2 bolts) from the patio to the garage, made her way through the garage (around lawnmowers, bikes, camping gear, tools etc) again stood on something to reach the bolt at the top of the garage door, and got out into the front garden and then to the street. She managed all this in the pitch dark. How she didn't fall and break her neck is a mystery still. Her only mistake was leaving her bedroom door open, so my husband spotted her empty bed when he got up to use the bathroom. He found her by chance when he saw her about to get into a taxi outside a house half way down the road from us - she had knocked on the door and persuaded the residents to phone a taxi for her.
The level of ingunuity needed for these escapes was unbelievable - at this stage, she could no longer work out how to make a cup of tea, but she could pull off escaping with ease, it seemed!