Peter died in 1725 at the relatively young age of 53. Russia ceased to build on Peter's reforms until the reign of Catherine II (Catherine the Great) in 1762.
There were 6 Tsars between Peter and Catherine, including three female rulers, viz Catherine I (Peter's widow) 1725-27, Anna (Peter's niece) 1730-40, and Elizabeth (Peter's own daughter) 1741-1762. Additionally there were three men/boys who died very soon after becoming Tsar. First was Peter II 1727-30 (Peter's grandson) who died as a teenager, Ivan VI (Peter's great great nephew) 1740-41 who was imprisoned for life as an infant and murdered in 1764, and finally Peter III (Peter's own grandson) 1762, who was overthrown, only months after his accession, in a coup staged by his wife and then murdered, probably with her complicity.
The wife who became CATHERINE the GREAT.
What a family!
Catherine the Great was not born Russian. She was a German Princess who became, arguably, Russia's greatest ever ruler. She was heavily influenced by The Enlightenment, and attempted to rule in the interests of even the lowliest of her people. However, Russia proved in the end too large a problem to be solved in one reign and by one person. The sadness for Russia was that it is still awaiting a natural successor to Catherine. Some might point at Alexander II, others at the short lived democracy between the first and the second revolutions of 1917, and others to Yeltsin, but the harsh reality is that Catherine, the last woman to rule Russia, in the final analysis failed, as Peter had done, to turn Russia into a 'modern' European country. It has always slipped back into the very worst forms of Russian Absolutism, under Alexander III, Stalin, and Putin.