The David Attenborough documentary series attracted 6.62m (27.2%) from 9pm, up 0.85m from the previous week.
That's Britain! earned 3.99m (17.1%) in the 8pm hour, with Who Do You Think You Are? USA generating 1.71m (13.7%) from 10.45pm.
ITV1 showed Champions League football for the majority of primetime. 3.54m (15%) turned up to see the clash between Bayer Leverkusen and Chelsea from 7.30pm, while 1.1m (8.2%) caught the highlights show UEFA Champions League: Extra Time.
BBC Two's Heir Hunters picked up 1.69m (7.69%) in the 7pm hour. MasterChef: The Professionals served 2.89m (12.4%) from 8pm, Your Money and How They Spend It rewarded 1.4m (5.8%) from 9pm and Life's Too Short amused 1.14m (5.8%) from 10pm.
Over on Channel 4, Kirstie's Handmade Britain had 1.62m (6.9%) from 8pm (+1: 187k/0.8%). Grand Designs took 2.09m (8.6%) in the 9pm hour (+1: 304k/1.7%) before Chris Moyles's Quiz Night entertained 1.31m (7.3%) with a further 149k (1.7%) on +1. Alan Carr: Chatty Man ended with 791k (8%) from 10.50pm.
Highland Emergency attended to 719k (3.2%) on Channel 5 from 7.30pm before Dangerous Drivers' School revved up 920k (3.95) from 8pm. Soho Blues was watched by 878k (3.6%) in the 9pm hour before Paul Merton's Adventures wrapped primetime up with 711k (4%).
Overall, BBC One (23.9%) eased ahead of ITV1 (15.5%; +1: 0.5%) in primetime. BBC Two took 8% to edge Channel 4, which had 6.5% (+1: 0.9%) and Channel 5 followed with 3.3%.
I'm a Celebrity... Get Me Out of Here Now! drew in 945k (5.4%) on ITV2 from 10pm.
BARB ratings data supplied by Attentional