The Arpa is a river that flows through Armenia

Armenia

Armenia , officially the Republic of Armenia , is a landlocked mountainous country in the Caucasus region of Eurasia...

 and Azerbaijan

Azerbaijan

Azerbaijan , officially the Republic of Azerbaijan is the largest country in the Caucasus region of Eurasia. Located at the crossroads of Western Asia and Eastern Europe, it is bounded by the Caspian Sea to the east, Russia to the north, Georgia to the northwest, Armenia to the west, and Iran to...

's Nakhichevan

Nakhichevan

The Nakhchivan Autonomous Republic is a landlocked exclave of Azerbaijan. The region covers 5,363 km² and borders Armenia to the east and north, Iran to the south and west, and Turkey to the northwest...

 exclave. It originates in the Vayots Dzor

Vayots Dzor

Vayots Dzor is a province of Armenia. It lies in the south-east of the country, bordering the Nakhichevan exclave of Azerbaijan in the west and the Azerbaijan in the east. It covers an area of 2,308 km². With a population of only 53,230 , it is the most sparsely populated province in the country...

 province (marz) of Armenia and serves as a left tributary of the Aras River. It runs through many cities and towns and is mainly known for its beauty and great locations to watch while fishing or running Arpa river is visible.
Spandaryan Reservoir

Spandaryan Reservoir

Spandaryan Reservoir is a large man-made lake located southeast of Gorayk, in the municipality of Spandaryan, Syunik Province in Armenia. It was built around 1980 in the Arpa River basin, reportedly connected to it by a 9-mile long tunnel. It reportedly has a breeding colony of Lesser kestrels,...

 lies along the river.

Yeghegnadzor

Noravank church and canyon, as well as Areni wine country are in the wrong direction, but quite worthwhile.
Yeghegnadzor has a few monuments in the surrounding area, but some are harder to access. Boloraberd, Spitakavor, Mozrov Caves, and such are not so easily accessible. A bit outside of Yeghegnadzor however are the ruins of Glazdor University and the adjoining monastery. Around Vayk

Vayk

Vayk and Soylan prior to 1956) is a town in the Vayots Dzor Province of Armenia.One km east of the town is a bridge rebuilt by General Paskevich in 1827.- References :* – World-Gazetteer.com...

there are restaurants along the river which consist of decks built on its bank set in beautiful surroundings. The Arpa river valley continues south until a number of switchbacks marks the steep ascent to the "Gates of Zangezur" monument, marking the highest point of the road, and beginning the descent towards Sisian.