A city designed to be looked at
Yerevan was largely replanned from the 1920s by the architect Alexander Tamanian, who imposed a radial layout and a palette of local volcanic tuff in pink, apricot and grey. Republic Square is that idea at full volume: a ring of tuff facades that turn rose-gold in late afternoon, with musical fountains running on summer evenings and the History Museum of Armenia anchoring one side.
The Cascade
A monumental limestone stairway climbing the hillside north of the centre, doubling as the Cafesjian Centre for the Arts. Sculpture terraces run the whole way up, contemporary galleries sit inside the structure, and the top gives you rooftops, Republic Square's grid and, on clear days, Mount Ararat. Ararat lies across the border in Turkey and cannot be visited from here, which tells you a great deal about Armenian history in a single view.
Substance behind the prettiness
The Matenadaran holds one of the world's great collections of ancient manuscripts, displayed in a fortress-like building at the top of Mashtots Avenue. Tsitsernakaberd, the Armenian Genocide Memorial and museum on a hill west of the centre, is sober, well curated and essential context for everything else you will see.
Easy, genuinely great day trips
The Hellenistic temple at Garni and the rock-cut monastery of Geghard pair into one half-day. Khor Virap frames Ararat about as well as any viewpoint on earth. Lake Sevan and the cathedral city of Echmiadzin are both straightforward returns.
Late spring and early autumn are the sweet spots: warm days, cool evenings, open terraces. July and August are hot and dry, often pushing into the mid-30s Celsius, and the city empties toward the mountains. Winter is properly cold with snow, but also when khash season and the wine bars come into their own.