2020. But thankfully it's beginning to recover in 2022. Romania has cities of great cultural interest (Bucharest, Constanța, Brașov, Iași, Timișoara, Cluj-Napoca or Alba Iulia), beaches and seaside resorts, ski resorts, and well-preserved rural regions appreciated for their beauty and tranquillity. Romania is the destination of many religious pilgrimages, hosting several thousands visitors each year. Currency The leu (pronounced ), plural: lei (); (ISO 4217 code RON; numeric code 946), "leo" (lion) in English is the currency of Romania. It is subdivided into 100 bani (singular: ban). On 1 July 2005, Romania underwent a currency reform, switching from the previous leu (ROL) to a new leu (RON). 1 RON is equal to 10,000 ROL. Romania joined the European Union on 1 January 2007 and initially hoped to adopt the euro in 2014, but with the deepening of the Euro crisis and with its own problems, such as a low workforce productivity, postponed its adoption plans indefinitely. As of February 2021, 1 RON is worth about 0.2045 EUR and US$0.2483. Romania is expected to adopt the euro in 2029. Fulfillment of the Maastricht criteria Romania, as a member state of the European Union, is required to adopt the common European currency, the Euro. For this reason Romania must fulfil the five Maastricht criteria, of which it met none as of June 2020. Natural resources Romania is an oil and gas producer. The pipeline network in Romania included 2,427 km for crude oil, 3,850 km for petroleum products, and 3,508 km for natural gas in 2006. Several major new pipelines are planned, especially the Nabucco Pipeline for Caspian oilfields, the longest one in the world. Romania could cash in four billion dollars from the Constanta-Trieste pipeline. Romania has considerable natural resources for a country of its size, including coal, iron ore, copper, chromium, uranium, antimony, mercury, gold, barite, borate, celestine (strontium), emery, feldspar, limestone, magnesite, marble, perlite, pumice, pyrites (sulfur), clay, arable land and hydropower. Romania's mineral production is adequate to supply its manufacturing output. Energy needs are also met by importing bituminous and anthracite coal and crude petroleum. In 2007 approximately 34 million tons of coal, approximately 4,000 tons of tungsten, 565,000 tons of iron ore, and 47,000 tons of zinc ore were mined. Lesser amounts of copper, lead, molybdenum, gold, silver, kaolin, and fluorite also were mined. Energy The energy sector is dominated by state-owned companies such as Termoelectrica, Hidroelectrica