Although it passes through both rugged mountainous and lowland terrain, it has no tunnels or valley bridges (except for some on the new National Road).

The National Road 90 is a large expressway on the West-East axis in Crete that connects the westernmost city and port, Kissamos with the easternmost, Sitia.

The tunnel in Vrachasi, Lassithi was built instead of a cutting through the mountain range of Anavlychos, because its unstable morphology would lead to landslides.

Although in recent centuries there were carriages and carts, there were no long-distance transport with them, due to lack of adequate road network in the rugged mountains of the island.

Contrary to what is believed by the locals, it was not invented during the years of the Colonial Junta, but during the government of the Center Union and specifically the idea belongs to Andreas Papandreou and Konstantinos Mitsotakis.

Eventually, however, the construction started from Chania, following the initiative of Mitsotakis, with the first contracts being assigned to the "Atlas" with Fotis Polatos as site manager in the Chania - Souda section and in the Ionios, TEGK and XEKTE in the Souda - Nio Chorio, Nio Chorio - Georgioupolis and Musela - Rethymnon sections.

The Pantanassa and Paleokastro bridges near Heraklion, 150 metres (490 ft) long each, were built in 1971, instead of landfilling the two respective valleys.

The Vrachasi tunnel, 285 metres (935 ft) long, was built in 1971-1973, instead of cutting into loose rocks, with the risk of landslides.