The highway starts in Tallinn and passes a number of notable towns, namely Kose, Põltsamaa, Tartu and Võru, with arterials branching off towards Paide, Valga, Põlva.

The main part is between Tallinn and Mäo, forming the longest continuous stretch of dual carriageway in Estonia.

[3] Future plans only envisage the construction of dual carriageways, albeit these have been largely put on hold due to austerity measures.

Hence the Tallinn-Mäo-Põltsamaa highway was rather used for traffic between Tallinn and Riga, with the route continuing towards Viljandi, Karksi-Nuia and the border at Polli.

The designed road had a width of 8 metres, with a granite foundation and topped with gravel, and a speed limit of 150 km/h.

Works continued towards Vaida but halted in 1993 due to economic downturn resulting from the collapse of the USSR, restarted and finished in 1997–1998.

By 2003, a section of dual carriageway was completed from Vaida to Aruvalla, but without grade-separated junctions or collectors.

Joining the EU provided the state access to development funding and large scale works on the aforementioned section began in 2007, which also saw an interchange constructed in Puurmani.

[8][9][10] 2010 saw the opening of Mäo interchange, a key junction for central Estonia, with the road rerouted and built from scratch as dual carriageway.

[11] Further works began in 2011 with dual carriageway extended from Aruvalla to Kose, finished in 2013, during which Estonia's first ecoduct was constructed.

[15] The largest road construction project in Estonian history began in 2017, extending the dual carriageway from Kose to Võõbu.

The highway was completely built from scratch on a new route, with interchanges, ecoducts, and electronic signage.

[18][19] The T2 (Estonian: põhimaantee 2) is a major north–southeast highway connecting the capital of the country, Tallinn, to the second largest city, Tartu and beyond into Põlva- and Võrumaa.

Bypassing Mäo, the T5 is met at an interchange, with the road transforming to single carriageway a few kilometres after.

The highway terminates in almost the very southern tip of Estonia, with border crossings to Latvia and Russia via the T7 only 18 and 2,5 km away, respectively.