Located near the Summer Garden is the Engineers Castle. It is actually Mikhailovsky Castle, but earned its nickname after being bestowed to the school of engineering. It was built for Paul I who lived in constant fear of assassination and never felt safe at the Winter Palace. The highly fortified palace was designed by architects, Vincenzo Brenna and Vasily Bajenov.

Completed in 1801 it was secure to the point of paranoia and surrounded on all sides by water. Unfortunately Paul didn't get to enjoy his new digs for long. The poor bastard was assassinated in his bed merely a month after moving into his fortress-like compound. A coup inspired by his son Alexander. I'll bet he didn't see that one coming. Seems Paul was correct to be so paranoid.