When it comes to the foreign exchange market, the London session stands as a prime time for trading. Positioned at the intersection of the Tokyo and New York sessions, this session sparks the dynamism behind the USD, EUR, GBP, and JPY – the world's most traded currencies. Consequently, the London session ignites heightened volatility, amplified volume, and constricts spreads during its active phase. As documented on Babypips, approximately 43% of all forex transactions unfold during the London session.

Proving to be one of the most favored among traders, the London session spans from 7 a.m. to 4 p.m. GMT (3 a.m. to 12 p.m. EST). This segment is further divided into three pivotal phases:

1. Pre-London Rush: At the tail end of the Tokyo session (6:00 a.m.–9:00 a.m.), market liquidity begins to surge, shaping the day's currency landscape.
2. The London-Tokyo Crossover: From 7:00 a.m. to 10:00 a.m., the London session intersects with the Tokyo session, catalyzing a substantial surge in volume and volatility during this two-hour stretch. This window is widely deemed the opportune moment for day traders.
3. Subsequently, at 12:00 p.m., volatility peaks as the New York session commences, overlapping with the London session.
4. Post-Peak Phase: Beyond 2:00 p.m., market volatility starts to recede as most lucrative trades have been executed, hence widening spreads.

Thus, the London session, due to its dual interaction with the Tokyo and New York sessions, emerges as the mecca of volatility, showcasing the world's most traded currencies in full swing.

Therefore, during the London session, the GBP and EUR pairs prominently shine. While monitoring all eight highly traded pairs is recommended, focusing on specific ones, namely:

1. EUR/USD
2. GBP/USD
3. EUR/GBP
4. GBP/CHF
5. EUR/CHF
6. USD/CHF
7. USD/JPY

During the London session, the market brims with heightened volatility, tight spreads, and substantial volume, rendering it an opportune window for trading endeavors.