Everything Nepal knows about earthquake safety was paid for in 1934 and 2015. Here is what happened, why it happened, and what those days still teach.
On a mild winter Monday afternoon, a roughly 300-km stretch of the Himalayan fault east of Kathmandu ruptured. The shaking lasted several minutes. In the Kathmandu Valley, entire bazaars of brick and timber collapsed; in the eastern Terai and Bihar, the ground itself failed — liquefaction tilted buildings whole and opened fissures across the plains.
More than 10,000 people died in Nepal and India together — over 8,500 of them in Nepal by most estimates. Kathmandu, Bhaktapur and Patan lost temples, towers and thousands of homes; the original Dharahara fell, as it would again 81 years later.
1934 remains the benchmark 'great earthquake' for the region: instrumental magnitude about 8.0, felt from Lhasa to Mumbai. Scientists estimate such eastern-Nepal ruptures recur on the order of centuries — the strain has been rebuilding ever since.
On a Saturday just before noon — schools closed, many people outdoors — the fault under central Nepal ruptured from Gorkha eastward, passing directly beneath the Kathmandu Valley. Nearly 9,000 people died and over 600,000 homes were destroyed, most of them unreinforced masonry in the hill districts.
The rupture unzipped eastward for about 140 km. Seventeen days later, on 12 May, its largest aftershock — M7.3 near Dolakha — brought down buildings the first quake had weakened. Aftershocks strong enough to feel continued for months; the sequence is still visible in this site's catalogue.
Landslides buried villages and blocked rivers; Langtang village was destroyed by a massive avalanche of ice and rock. Yet the timing — midday, weekend — and decades of retrofitting schools prevented a far worse toll. Engineers estimate a nighttime rupture could have doubled it.
In both disasters, almost every death traced back to unreinforced masonry. A retrofitted room is worth more than any app — check your building.
2015's deadliest surprise came 17 days later. After any big quake, treat weakened buildings as dangerous and expect strong aftershocks for weeks.
2015 struck at Saturday midday and spared thousands of schoolchildren. You can't schedule the next one; you can practise the drill and pack the bag.
The 2015 rupture stopped short of western Nepal, where no great quake has struck since 1505. That stored energy is why preparedness matters most in the west.
Figures are widely reported estimates (USGS, NSET, Government of Nepal PDNA); sources vary — see About for data notes.
Ten minutes today: run the family drill, check your building, pack the bag.